Tüm alıştırma soruları

5556 soru

Soru 2021Soru
For all non-zero real numbers aa, bb, and cc, the expression below is simplified:
(2a2b1c3)34a5(b2c2)2\frac{(2a^2 b^{-1} c^3)^3}{4a^5 (b^2 c^{-2})^{-2}}
Which of the following is equivalent to this expression?
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Cevap: 2abc52abc^5

Cevap

The expression is equivalent to 2abc52abc^5.
The correct answer is obtained by first simplifying the numerator and denominator using the power of a product and power of a power rules, then dividing the coefficients and subtracting the exponents of like bases. This yields the simplified expression 2abc52abc^5.

Adım Adım Çözüm

1
Apply the power of a product rule to the numerator.
(2a2b1c3)3=23(a2)3(b1)3(c3)3=8a6b3c9(2a^2 b^{-1} c^3)^3 = 2^3 \cdot (a^2)^3 \cdot (b^{-1})^3 \cdot (c^3)^3 = 8 a^6 b^{-3} c^9
Each factor inside the parentheses must be raised to the power of 3, multiplying the exponents of the variables.
2
Apply the power of a product rule to the denominator's parentheses.
4a5(b2c2)2=4a5(b2)2(c2)2=4a5b4c44a^5 (b^2 c^{-2})^{-2} = 4a^5 \cdot (b^2)^{-2} \cdot (c^{-2})^{-2} = 4a^5 b^{-4} c^4
The terms inside the parentheses are raised to the power of -2, multiplying their exponents.
3
Divide the simplified numerator by the simplified denominator.
2a1b1c52a^1 b^1 c^5, which is 2abc52abc^5
Divide the coefficients (8 / 4 = 2) and subtract the exponents of the same bases: a65=a1a^{6-5} = a^1, b3(4)=b1b^{-3 - (-4)} = b^1, and c94=c5c^{9-4} = c^5.

Anahtar Kavram

Properties of Exponents in Algebraic Expressions

Alternatif Yöntem

Alternatively, you can rewrite the expression by eliminating negative exponents first. Convert b1b^{-1} to 1b\frac{1}{b}, b2b^2 to itself, and c2c^{-2} to 1c2\frac{1}{c^2} within the parentheses, apply the outer exponents, and then simplify the resulting complex fraction.
Tahmini Süre:1m 30s
Soru 2022Soru

Two polynomial expressions are defined as P(x)=(2x4)(x25x+c)P(x) = (2x - 4)(x^2 - 5x + c) and Q(x)=(x2+3x4)(2x+a)Q(x) = (x^2 + 3x - 4)(2x + a), where aa and cc are constants. When P(x)P(x) is expanded and simplified, it has no xx term. If the coefficient of the x2x^2 term in the expanded and simplified form of Q(x)Q(x) is equal to the coefficient of the x2x^2 term in the expanded and simplified form of P(x)P(x), what is the value of aa?

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Cevap: -20

Cevap

The value of aa is 20-20.
Expanding P(x)=(2x4)(x25x+c)P(x) = (2x - 4)(x^2 - 5x + c) yields 2x314x2+(2c+20)x4c2x^3 - 14x^2 + (2c + 20)x - 4c. Since there is no xx term, 2c+20=02c + 20 = 0, which means c=10c = -10. This leaves the coefficient of the x2x^2 term in P(x)P(x) as 14-14. Expanding Q(x)=(x2+3x4)(2x+a)Q(x) = (x^2 + 3x - 4)(2x + a) yields 2x3+(a+6)x2+(3a8)x4a2x^3 + (a + 6)x^2 + (3a - 8)x - 4a, so the coefficient of its x2x^2 term is a+6a + 6. Setting a+6=14a + 6 = -14 and solving for aa gives a=20a = -20.

Adım Adım Çözüm

1
Expand the polynomial P(x)=(2x4)(x25x+c)P(x) = (2x - 4)(x^2 - 5x + c) using the distributive property.
P(x)=2x314x2+(2c+20)x4cP(x) = 2x^3 - 14x^2 + (2c + 20)x - 4c
To identify the coefficients of each term in P(x)P(x).
2
Set the coefficient of the xx term, 2c+202c + 20, to 00 and solve for cc.
c=10c = -10
The problem states that P(x)P(x) has no xx term when simplified, which means its coefficient must be zero.
3
Determine the coefficient of the x2x^2 term in P(x)P(x).
The coefficient of x2x^2 is 14-14.
This coefficient will be equated to the x2x^2 coefficient of Q(x)Q(x) as per the problem constraints.
4
Expand the polynomial Q(x)=(x2+3x4)(2x+a)Q(x) = (x^2 + 3x - 4)(2x + a) using the distributive property.
Q(x)=2x3+(a+6)x2+(3a8)x4aQ(x) = 2x^3 + (a + 6)x^2 + (3a - 8)x - 4a
To identify the coefficient of the x2x^2 term in Q(x)Q(x).
5
Set the coefficient of the x2x^2 term in Q(x)Q(x), which is a+6a + 6, equal to the coefficient of the x2x^2 term in P(x)P(x), which is 14-14, and solve for aa.
a=20a = -20
The problem states that these two coefficients are equal.

Anahtar Kavram

Operations on Polynomials
Tahmini Süre:2m 30s
Soru 2023Soru

In the standard (x,y)(x, y) coordinate plane, a circle is defined by the equation x2+y2=17x^2 + y^2 = 17 and a line is defined by the equation y=x3y = x - 3. If (x,y)(x, y) represents the intersection point of the circle and the line that lies in the first quadrant, what is the value of x+yx + y?

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Cevap: 5

Cevap

The sum of the coordinates of the first-quadrant intersection point is 5.
The correct answer is the sum of the coordinates of the first-quadrant intersection point. By substituting y=x3y = x - 3 into the circle's equation, we get x2+(x3)2=17x^2 + (x - 3)^2 = 17. Expanding the squared term gives x2+x26x+9=17x^2 + x^2 - 6x + 9 = 17, which simplifies to 2x26x8=02x^2 - 6x - 8 = 0. Dividing the entire equation by 2 yields x23x4=0x^2 - 3x - 4 = 0. Factoring this quadratic equation gives (x4)(x+1)=0(x - 4)(x + 1) = 0, which has solutions x=4x = 4 and x=1x = -1. Because the intersection point must lie in the first quadrant, the xx-coordinate must be positive, so we choose x=4x = 4. Substituting x=4x = 4 back into the linear equation gives y=43=1y = 4 - 3 = 1. The sum of these coordinates is 4+1=54 + 1 = 5.

Adım Adım Çözüm

1
Substitute the expression for yy from the linear equation into the circle's equation.
x2+(x3)2=17x^2 + (x - 3)^2 = 17
This eliminates yy so that we can solve for xx.
2
Expand the squared binomial and combine like terms to write the equation in standard quadratic form.
2x26x8=02x^2 - 6x - 8 = 0
Expanding (x3)2(x - 3)^2 gives x26x+9x^2 - 6x + 9, and adding x2x^2 and subtracting 17 from both sides gives the quadratic equation.
3
Simplify the quadratic equation by dividing all terms by 2, then factor the resulting quadratic expression.
(x4)(x+1)=0(x - 4)(x + 1) = 0
Dividing by 2 gives x23x4=0x^2 - 3x - 4 = 0, which factors into (x4)(x+1)=0(x - 4)(x + 1) = 0 since (4)×1=4(-4) \times 1 = -4 and 4+1=3-4 + 1 = -3.
4
Solve for xx and select the positive solution since the point lies in the first quadrant.
x=4x = 4
The solutions are x=4x = 4 and x=1x = -1. In the first quadrant, both coordinates must be positive, so we choose x=4x = 4.
5
Substitute x=4x = 4 back into the linear equation to find the corresponding yy-coordinate.
y=1y = 1
Using y=x3y = x - 3 with x=4x = 4 gives y=43=1y = 4 - 3 = 1.
6
Calculate the sum of the coordinates x+yx + y.
4+1=54 + 1 = 5
The question asks for the value of x+yx + y.

Anahtar Kavram

Solving a system consisting of a linear equation and a quadratic circle equation by substitution, factoring the resulting quadratic equation, and applying quadrant constraints.
Soru 2024Soru

A rectangle has a length of y+7y + 7 inches and a width of y3y - 3 inches. Which of the following expressions represents the area, in square inches, of the rectangle?

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Cevap: y^2 + 4y - 21

Cevap

The expression y2+4y21y^2 + 4y - 21
The area of a rectangle is found by multiplying its length by its width. The product of the dimensions is represented by the expression (y+7)(y3)(y + 7)(y - 3). Applying the distributive property gives y23y+7y21y^2 - 3y + 7y - 21. Combining the like terms 3y-3y and 7y7y results in +4y+4y. Therefore, the simplified expression for the area is y2+4y21y^2 + 4y - 21.

Adım Adım Çözüm

1
Set up the area formula for the rectangle by multiplying its length and width.
Area =(y+7)(y3)= (y + 7)(y - 3)
The area of a rectangle is calculated by multiplying its length by its width.
2
Use the distributive property to expand the product of the two binomials.
Area =y(y)+y(3)+7(y)+7(3)=y23y+7y21= y(y) + y(-3) + 7(y) + 7(-3) = y^2 - 3y + 7y - 21
Each term in the first binomial must be multiplied by each term in the second binomial.
3
Combine the like terms to simplify the expression into standard form.
Area =y2+4y21= y^2 + 4y - 21
Combining 3y-3y and +7y+7y yields +4y+4y.

Anahtar Kavram

Finding the area of a rectangle by multiplying binomial expressions using the distributive property.
Tahmini Süre:45s
Soru 2025Soru

Two functions, ff and gg, are defined as f(x)=(x4)2f(x) = (x - 4)^2 and g(x)=2x3g(x) = |2x - 3|. What is the value of the composite function f(g(x))f(g(x)) evaluated at x=1x = -1?

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Cevap: 1

Cevap

1
To find f(g(1))f(g(-1)), we first evaluate the inner function gg at x=1x = -1. Substituting 1-1 into g(x)=2x3g(x) = |2x - 3| gives g(1)=2(1)3=5=5g(-1) = |2(-1) - 3| = |-5| = 5. Next, we use this result as the input for the outer function ff, evaluating f(5)f(5). Substituting 55 into f(x)=(x4)2f(x) = (x - 4)^2 gives f(5)=(54)2=12=1f(5) = (5 - 4)^2 = 1^2 = 1. This corresponds to the option with value 1.

Adım Adım Çözüm

1
Evaluate the inner function g(1)g(-1) first.
g(1)=2(1)3=23=5=5g(-1) = |2(-1) - 3| = |-2 - 3| = |-5| = 5
The input to the outer function of a composition is the output of the inner function.
2
Evaluate the outer function f(x)f(x) at the result from the previous step.
f(5)=(54)2=12=1f(5) = (5 - 4)^2 = 1^2 = 1
We substitute the value of g(1)g(-1), which is 55, into the function f(x)f(x) to find the final value of the composition.

Anahtar Kavram

Evaluating a composite function involves applying the inner function first, then using that output as the input for the outer function.
Soru 2026Soru

A construction company is working on two building projects, Project X and Project Y. The quantities of concrete (in tons) and steel (in tons) required for these projects are represented by the matrix QQ:

Q=[802512040]Q = \begin{bmatrix} 80 & 25 \\ 120 & 40 \end{bmatrix}

where the first row represents Project X, the second row represents Project Y, the first column represents concrete, and the second column represents steel.

The purchase cost per ton and the transportation cost per ton for these materials are represented by the matrix CC:

C=[1101565045]C = \begin{bmatrix} 110 & 15 \\ 650 & 45 \end{bmatrix}

where the first row represents concrete, the second row represents steel, the first column represents the purchase cost (in dollars per ton), and the second column represents the transportation cost (in dollars per ton).

If the product matrix P=QCP = QC represents the total cost details for the two projects, what is the total transportation cost for Project Y, in dollars?

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Cevap: 3600

Cevap

The total transportation cost for Project Y is 3,600 dollars.
The correct answer is 3,600. To find the total transportation cost for Project Y, we calculate the entry in the second row (Project Y) and second column (transportation cost) of the product matrix P=QCP = QC. This is calculated as 120 tons of concrete×15 dollars per ton+40 tons of steel×45 dollars per ton=1,800+1,800=3,600120 \text{ tons of concrete} \times 15 \text{ dollars per ton} + 40 \text{ tons of steel} \times 45 \text{ dollars per ton} = 1,800 + 1,800 = 3,600 dollars.

Adım Adım Çözüm

1
Identify the row representing Project Y and the column representing transportation cost
Row 2 of QQ is [120,40][120, 40] and Column 2 of CC is [15,45]T[15, 45]^T.
To find the total transportation cost for Project Y, we must compute the entry in the second row (Project Y) and second column (transportation cost) of the product matrix P=QCP = QC.
2
Multiply the row elements by the corresponding column elements
120×15=1800120 \times 15 = 1800 and 40×45=180040 \times 45 = 1800
This calculates the individual transportation costs for the concrete and steel required for Project Y.
3
Sum the products to find the total transportation cost
1800+1800=36001800 + 1800 = 3600
Adding these individual costs gives the total transportation cost for Project Y.

Anahtar Kavram

Matrix multiplication involves multiplying the elements of each row of the first matrix by the corresponding elements of each column of the second matrix and summing the products.
Soru 2027Soru

If 32x1=273^{2x - 1} = 27, what is the value of xx?

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Cevap: 2

Cevap

The value of xx is 22.
Rewriting 2727 as 333^3 gives the equation 32x1=333^{2x - 1} = 3^3. Equating the exponents yields 2x1=32x - 1 = 3, which solves to x=2x = 2.

Adım Adım Çözüm

1
Rewrite the right side of the equation with a base of 33.
32x1=333^{2x - 1} = 3^3
Expressing both sides of the equation with a common base allows for direct comparison of the exponents.
2
Set the exponents equal to each other.
2x1=32x - 1 = 3
Since the bases are both 33, their exponents must be equal for the expressions to be equal.
3
Solve the linear equation for xx.
x=2x = 2
Adding 11 to both sides gives 2x=42x = 4. Dividing both sides by 22 results in x=2x = 2.

Anahtar Kavram

Solving exponential equations by expressing both sides with a common base
Soru 2028Soru

If xx is a real number such that (3x)492x27x1=81\frac{(3^x)^4 \cdot 9^{2-x}}{27^{x-1}} = 81, what is the value of xx?

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Cevap: 3

Cevap

The value of xx is 3.
Rewriting the bases in terms of 3, the expression becomes 34x342x33x3=34\frac{3^{4x} \cdot 3^{4-2x}}{3^{3x-3}} = 3^4. Combining the numerator using the product rule gives 32x+43^{2x+4} in the numerator. Dividing by the denominator using the quotient rule gives 3(2x+4)(3x3)=3x+73^{(2x+4)-(3x-3)} = 3^{-x+7}. Equating this to 343^4 gives x+7=4-x + 7 = 4, which yields x=3x = 3.

Adım Adım Çözüm

1
Express each base in terms of the common base 3
9=329 = 3^2, 27=3327 = 3^3, and 81=3481 = 3^4
Converting all terms to a common base allows the use of exponent rules to combine them.
2
Apply the power of a power rule (bm)n=bmn(b^m)^n = b^{mn} to rewrite each exponent
(3x)4=34x(3^x)^4 = 3^{4x}, (32)2x=342x(3^2)^{2-x} = 3^{4-2x}, and (33)x1=33x3(3^3)^{x-1} = 3^{3x-3}
This simplifies individual terms by multiplying their exponents.
3
Apply the product rule of exponents bmbn=bm+nb^m \cdot b^n = b^{m+n} to combine the terms in the numerator
34x342x=34x+42x=32x+43^{4x} \cdot 3^{4-2x} = 3^{4x + 4 - 2x} = 3^{2x + 4}
Multiplying exponential terms with the same base is simplified by adding their exponents.
4
Apply the quotient rule of exponents bmbn=bmn\frac{b^m}{b^n} = b^{m-n} to simplify the fraction
3(2x+4)(3x3)=3x+73^{(2x+4) - (3x-3)} = 3^{-x+7}
Dividing exponential terms with the same base is simplified by subtracting the exponent in the denominator from the exponent in the numerator.
5
Equate the exponents of the simplified base 3 expression and base 3 representation of 81
x+7=4-x + 7 = 4, which solves to x=3x = 3
Since the bases are equal, the powers must be equal for the equation to hold true.

Anahtar Kavram

Properties of Exponents in Algebraic Expressions
Soru 2029Soru

An entrepreneur starts a company with an operating budget of 100,000100,000 in its first year. For each of the next 4 years (years 2 through 5), the budget increases by a constant amount of dd dollars each year. For years 6 through 8, the budget increases geometrically, where the budget in year 6 is 1.51.5 times the budget in year 5, and the budget increases by 50%50\% each year thereafter. If the total operating budget over the first 8 years is 1,597,5001,597,500 dollars, what is the value of dd?

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Cevap: 10,00010,000

Cevap

The common difference is 10,00010,000.
The correct answer is found by setting up the sum of the first 5 years of the arithmetic sequence and the subsequent 3 years of the geometric sequence. Summing the expressions for all 8 years gives 1,212,500+38.5d1,212,500 + 38.5d. Equating this expression to the total budget of 1,597,5001,597,500 and solving for dd yields 10,00010,000.

Adım Adım Çözüm

1
Express the budget for the first 5 years as an arithmetic sequence and find their sum.
S5=100,000+(100,000+d)+(100,000+2d)+(100,000+3d)+(100,000+4d)=500,000+10dS_5 = 100,000 + (100,000 + d) + (100,000 + 2d) + (100,000 + 3d) + (100,000 + 4d) = 500,000 + 10d
The budget starts at 100,000100,000 in year 1 and increases by a constant amount dd each year through year 5.
2
Express the budgets for years 6 through 8 as a geometric sequence starting from 1.51.5 times the year 5 budget.
Year 6: 1.5(100,000+4d)=150,000+6d1.5(100,000 + 4d) = 150,000 + 6d; Year 7: 1.5(150,000+6d)=225,000+9d1.5(150,000 + 6d) = 225,000 + 9d; Year 8: 1.5(225,000+9d)=337,500+13.5d1.5(225,000 + 9d) = 337,500 + 13.5d. The sum of these 3 years is 712,500+28.5d712,500 + 28.5d.
The budget increases by a factor of 1.51.5 (or 50%50\%) each year starting from year 6.
3
Combine the sums of both sequences to represent the total 8-year budget and solve for dd.
Total = (500,000+10d)+(712,500+28.5d)=1,212,500+38.5d(500,000 + 10d) + (712,500 + 28.5d) = 1,212,500 + 38.5d. Setting this equal to the given total: 1,212,500+38.5d=1,597,500    38.5d=385,000    d=10,0001,212,500 + 38.5d = 1,597,500 \implies 38.5d = 385,000 \implies d = 10,000.
The total budget over the 8 years is the sum of the budgets of the individual years.

Anahtar Kavram

Combining arithmetic and geometric sequences in multi-step word problems.

Alternatif Yöntem

Instead of calculating each geometric year sequentially, the sum of the geometric sequence for years 6 to 8 can be calculated using the geometric series sum formula Sn=a11rn1rS_n = a_1 \frac{1 - r^n}{1 - r} with a1=1.5(100,000+4d)a_1 = 1.5(100,000 + 4d) and r=1.5r = 1.5 over n=3n = 3 terms.
Tahmini Süre:2m 30s
Soru 2030Soru

A local farm sells organic fruit baskets at a weekend market. The number of small and large baskets sold on Saturday and Sunday is represented by matrix QQ, where row 1 represents Saturday, row 2 represents Sunday, column 1 represents small baskets, and column 2 represents large baskets:

Q=[40302050]Q = \begin{bmatrix} 40 & 30 \\ 20 & 50 \end{bmatrix}

The selling price and the production cost, in dollars, for each type of basket are represented by matrix PP, where row 1 represents small baskets, row 2 represents large baskets, column 1 represents the selling price, and column 2 represents the production cost:

P=[1582512]P = \begin{bmatrix} 15 & 8 \\ 25 & 12 \end{bmatrix}

The product matrix R=QPR = QP represents the total revenue and total production cost for each day. Which of the following matrices represents RR?

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Cevap: [13506801550760]\begin{bmatrix} 1350 & 680 \\ 1550 & 760 \end{bmatrix}

Cevap

[13506801550760]\begin{bmatrix} 1350 & 680 \\ 1550 & 760 \end{bmatrix}
The correct product matrix is obtained by performing matrix multiplication QPQP. Multiplying the first row of QQ by the first column of PP yields the Saturday revenue: 40×15+30×25=135040 \times 15 + 30 \times 25 = 1350. Multiplying the first row of QQ by the second column of PP yields the Saturday cost: 40×8+30×12=68040 \times 8 + 30 \times 12 = 680. Repeating this for the second row of QQ (Sunday) yields the Sunday revenue of 15501550 and Sunday cost of 760760. Thus, the resulting matrix is the one with row 1 equal to [1350,680][1350, 680] and row 2 equal to [1550,760][1550, 760].

Adım Adım Çözüm

1
Set up the matrix multiplication product R=QPR = QP.
R=[40302050][1582512]R = \begin{bmatrix} 40 & 30 \\ 20 & 50 \end{bmatrix} \begin{bmatrix} 15 & 8 \\ 25 & 12 \end{bmatrix}
To find the total revenue and production cost for Saturday and Sunday, we must multiply the quantity matrix by the price-cost matrix.
2
Calculate the elements of the first row of the product matrix RR, representing Saturday's revenue and cost.
Row 1, Column 1 (Saturday Revenue): 40(15)+30(25)=600+750=135040(15) + 30(25) = 600 + 750 = 1350. Row 1, Column 2 (Saturday Cost): 40(8)+30(12)=320+360=68040(8) + 30(12) = 320 + 360 = 680.
Multiply the first row of matrix QQ by the columns of matrix PP to determine Saturday's financial values.
3
Calculate the elements of the second row of the product matrix RR, representing Sunday's revenue and cost.
Row 2, Column 1 (Sunday Revenue): 20(15)+50(25)=300+1250=155020(15) + 50(25) = 300 + 1250 = 1550. Row 2, Column 2 (Sunday Cost): 20(8)+50(12)=160+600=76020(8) + 50(12) = 160 + 600 = 760.
Multiply the second row of matrix QQ by the columns of matrix PP to determine Sunday's financial values.
4
Combine the calculated elements into the final 2×22 \times 2 matrix.
[13506801550760]\begin{bmatrix} 1350 & 680 \\ 1550 & 760 \end{bmatrix}
Placing the values in their corresponding row and column positions yields the complete product matrix.

Anahtar Kavram

Matrix Multiplication in Applied Word Problems
Tahmini Süre:1m 30s
Soru 2031Soru

A line intersects a parabola at two distinct points in the standard (x,y)(x, y) coordinate plane. The system of equations representing these curves is given by:

x27x+3y=63y4x=6\begin{aligned} x^2 - 7x + 3y &= 6 \\ 3y - 4x &= 6 \end{aligned}

What is the distance between the two intersection points?

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Cevap: 5

Cevap

5
Solving the system of equations yields the intersection points (0,2)(0, 2) and (3,6)(3, 6). The distance between these points is computed using the distance formula: (30)2+(62)2=25=5\sqrt{(3 - 0)^2 + (6 - 2)^2} = \sqrt{25} = 5.

Adım Adım Çözüm

1
Isolate the 3y3y term in the linear equation.
3y=4x+63y = 4x + 6
This allows for a direct substitution into the quadratic equation without introducing fractional coefficients.
2
Substitute 3y3y into the first equation and simplify.
x23x=0x^2 - 3x = 0
Substituting 4x+64x + 6 for 3y3y yields x27x+(4x+6)=6x^2 - 7x + (4x + 6) = 6. Subtracting 6 from both sides and combining like terms simplifies this to a basic quadratic equation.
3
Solve the quadratic equation for xx and determine the corresponding yy-coordinates.
The intersection points are (0,2)(0, 2) and (3,6)(3, 6).
Factoring gives x(x3)=0x(x - 3) = 0, so the xx-coordinates are 00 and 33. Substituting x=0x = 0 into the linear relation gives 3y=6    y=23y = 6 \implies y = 2. Substituting x=3x = 3 gives 3y=18    y=63y = 18 \implies y = 6.
4
Calculate the distance between the two coordinates.
5
Using the distance formula: d=(30)2+(62)2=9+16=5d = \sqrt{(3 - 0)^2 + (6 - 2)^2} = \sqrt{9 + 16} = 5.

Anahtar Kavram

Systems of Linear and Non-Linear Equations
Soru 2032Soru

What is the greatest integer value of xx that satisfies the inequality 25x3x423\frac{2 - 5x}{3} - \frac{x - 4}{2} \geq 3?

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Cevap: -1

Cevap

The greatest integer value of xx that satisfies the inequality is -1.
The correct answer is -1 because solving the inequality leads to x213x \leq -\frac{2}{13}. Since 213-\frac{2}{13} is approximately 0.154-0.154, the set of integers satisfying the inequality is {1,2,3,}\{-1, -2, -3, \dots\}. The greatest integer in this set is -1.

Adım Adım Çözüm

1
Multiply the entire inequality by the least common multiple of the denominators (6) to eliminate the fractions.
2(25x)3(x4)182(2 - 5x) - 3(x - 4) \geq 18
Multiplying by a positive number clears the fractions without changing the direction of the inequality.
2
Distribute the coefficients and combine like terms on the left side of the inequality.
1613x1816 - 13x \geq 18
Simplifying the expressions on each side makes it easier to isolate the variable.
3
Subtract 16 from both sides to isolate the term with the variable xx.
13x2-13x \geq 2
Moving the constant terms to one side prepares the inequality for division.
4
Divide both sides by -13 and reverse the direction of the inequality sign.
x213x \leq -\frac{2}{13}
Dividing by a negative number requires flipping the inequality sign to maintain a true statement.
5
Determine the greatest integer that is less than or equal to 213-\frac{2}{13}.
-1
Since 2130.154-\frac{2}{13} \approx -0.154, the largest integer that is less than or equal to this value is -1.

Anahtar Kavram

Solving multi-step linear inequalities, including clearing fractional coefficients and reversing the inequality sign when multiplying or dividing by a negative number.
Soru 2033Soru

What is the value of the discriminant of the quadratic equation 3x2+5x2=03x^2 + 5x - 2 = 0?

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Cevap: 49

Cevap

The discriminant of the quadratic equation is 49.
The discriminant is calculated using the formula b24acb^2 - 4ac. For the equation 3x2+5x2=03x^2 + 5x - 2 = 0, the coefficients are a=3a = 3, b=5b = 5, and c=2c = -2. Substituting these yields 524(3)(2)=25(24)=25+24=495^2 - 4(3)(-2) = 25 - (-24) = 25 + 24 = 49.

Adım Adım Çözüm

1
Identify the coefficients of the quadratic equation 3x2+5x2=03x^2 + 5x - 2 = 0 in the standard form ax2+bx+c=0ax^2 + bx + c = 0.
a=3a = 3, b=5b = 5, and c=2c = -2
To use the discriminant formula, we must first extract the constant coefficients corresponding to each term.
2
Substitute the coefficients into the discriminant formula D=b24acD = b^2 - 4ac.
D=524(3)(2)=25(24)=25+24=49D = 5^2 - 4(3)(-2) = 25 - (-24) = 25 + 24 = 49
Calculating the value of the discriminant provides the required solution.

Anahtar Kavram

Calculating the discriminant of a quadratic equation to determine the nature of its roots.
Soru 2034Soru

What is the maximum integer value of kk that satisfies the inequality 85k>288 - 5k > 28?

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Cevap: -5

Cevap

The maximum integer value that satisfies the inequality is 5-5.
Subtracting 8 from both sides of the inequality 85k>288 - 5k > 28 yields 5k>20-5k > 20. Dividing both sides of the inequality by 5-5 and reversing the inequality sign results in k<4k < -4. The largest integer strictly less than 4-4 is 5-5.

Adım Adım Çözüm

1
Subtract 8 from both sides of the inequality.
5k>20-5k > 20
To isolate the term with the variable on the left side of the inequality.
2
Divide both sides by 5-5 and reverse the inequality sign.
k<4k < -4
Dividing both sides of an inequality by a negative number requires reversing the direction of the inequality symbol.
3
Determine the largest integer strictly less than 4-4.
5-5
Because the inequality is strict (<<), the value of kk cannot be equal to 4-4. The greatest integer less than 4-4 is 5-5.

Anahtar Kavram

Solving linear inequalities and reversing the inequality sign when dividing by a negative number.
Soru 2035Soru

Consider the functions f(x)=x+3x1f(x) = \frac{x+3}{x-1}, where x1x \neq 1, and g(x)=x2x4g(x) = x^2 - x - 4. If xx is an integer such that the composite function evaluation g(f(g(x)))=16g(f(g(x))) = 16, what is the product of all such integer values of xx?

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Cevap: -6

Cevap

The product of all integer values of xx that satisfy the equation is 6-6.
Solving the nested composite equation g(f(g(x)))=16g(f(g(x))) = 16 systematically yields the integer solutions x=3x = 3 and x=2x = -2. The product of these values is 6-6.

Adım Adım Çözüm

1
Set u=f(g(x))u = f(g(x)) and solve the outer quadratic equation g(u)=16g(u) = 16.
u=5u = 5 or u=4u = -4
This simplifies the nested composition into a single-variable quadratic equation.
2
Set v=g(x)v = g(x) and solve the rational equations f(v)=5f(v) = 5 and f(v)=4f(v) = -4.
v=2v = 2 or v=0.2v = 0.2
This determines the required outputs of the function g(x)g(x) that will satisfy the composite equation.
3
Solve the quadratic equations g(x)=2g(x) = 2 and g(x)=0.2g(x) = 0.2 for xx.
x=3x = 3, x=2x = -2, or x=5±44510x = \frac{5 \pm \sqrt{445}}{10}
This finds all real values of xx that satisfy the composite equation.
4
Identify the integer values from the solution set and compute their product.
3×(2)=63 \times (-2) = -6
The question specifically requests the product of the integer values of xx.

Anahtar Kavram

Function composition and multi-step equation solving
Soru 2036Soru

For a constant kk, the quadratic equation 13x2k6x+(k10)=0\frac{1}{3}x^2 - \frac{k}{6}x + (k - 10) = 0 has two real roots, r1r_1 and r2r_2. If the sum of the reciprocals of the roots, 1r1+1r2\frac{1}{r_1} + \frac{1}{r_2}, is equal to 12-\frac{1}{2}, what is the value of kk?

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Cevap: 7.5

Cevap

The value of kk is 7.57.5.
By writing the sum of the reciprocals in terms of the sum and product of the roots, we find that 1r1+1r2=r1+r2r1r2\frac{1}{r_1} + \frac{1}{r_2} = \frac{r_1 + r_2}{r_1 r_2}. Substituting the values from Vieta's formulas (r1+r2=k2r_1 + r_2 = \frac{k}{2} and r1r2=3(k10)r_1 r_2 = 3(k - 10)) yields k6(k10)=12\frac{k}{6(k - 10)} = -\frac{1}{2}. Solving this equation for kk results in k=7.5k = 7.5.

Adım Adım Çözüm

1
Identify the quadratic coefficients in terms of the constant kk.
a=13a = \frac{1}{3}, b=k6b = -\frac{k}{6}, and c=k10c = k - 10
Applying Vieta's formulas requires the coefficients from the standard form ax2+bx+c=0ax^2 + bx + c = 0.
2
Determine the sum and the product of the roots using Vieta's formulas.
r1+r2=k2r_1 + r_2 = \frac{k}{2} and r1r2=3(k10)r_1 r_2 = 3(k - 10)
Vieta's formulas state that the sum of the roots is ba-\frac{b}{a} and the product of the roots is ca\frac{c}{a}.
3
Express the sum of the reciprocals of the roots in terms of kk.
1r1+1r2=r1+r2r1r2=k6(k10)\frac{1}{r_1} + \frac{1}{r_2} = \frac{r_1 + r_2}{r_1 r_2} = \frac{k}{6(k - 10)}
Finding a common denominator allows the sum of the reciprocals to be written as the ratio of the sum of the roots to the product of the roots.
4
Equate the expression to 12-\frac{1}{2} and solve the resulting equation for kk.
k=7.5k = 7.5
Solving k6(k10)=12\frac{k}{6(k - 10)} = -\frac{1}{2} gives 2k=6(k10)    8k=60    k=7.52k = -6(k - 10) \implies 8k = 60 \implies k = 7.5.

Anahtar Kavram

Vieta's Formulas and Algebraic Relationships of Roots
Tahmini Süre:2m 30s
Soru 2037Soru

For the opening night of a school play, a total of 320320 tickets were sold, raising a total of $2140\$2{}140 in ticket sales. Student tickets were sold for $5\$5 each, and adult tickets were sold for $8\$8 each. How many adult tickets were sold?

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Cevap: 180

Cevap

180
The correct answer is 180180. By setting up a single-variable linear equation where aa represents the number of adult tickets, the problem translates to 8a+5(320a)=21408a + 5(320 - a) = 2140. Simplifying this yields 3a+1600=21403a + 1600 = 2140, which simplifies to 3a=5403a = 540 and results in a=180a = 180.

Adım Adım Çözüm

1
Define variables for the unknown quantities based on the given total.
Let aa represent the number of adult tickets sold. The number of student tickets sold is represented as 320a320 - a.
Since the total number of tickets is 320320, subtracting the number of adult tickets from the total yields the number of student tickets.
2
Construct a linear equation using the ticket prices and the total revenue.
8a+5(320a)=21408a + 5(320 - a) = 2140
Multiplying the quantity of each ticket type by its respective price (88 dollars for adult and 55 dollars for student) yields the total ticket sales revenue of 2,1402,140 dollars.
3
Solve the equation for the variable aa.
8a+16005a=2140    3a+1600=2140    3a=540    a=1808a + 1600 - 5a = 2140 \implies 3a + 1600 = 2140 \implies 3a = 540 \implies a = 180
Apply the distributive property, group like terms, isolate the variable term, and divide to solve for the number of adult tickets.

Anahtar Kavram

Translating word problems into a single-variable linear equation and solving for the unknown quantity.
Soru 2038Soru

If log5x=3\log_5 x = 3, what is the value of xx?

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Cevap: 125

Cevap

125
To solve the logarithmic equation log5x=3\log_5 x = 3, we apply the fundamental definition of a logarithm. A logarithmic equation of the form logbx=y\log_b x = y can be rewritten in exponential form as by=xb^y = x. In this equation, the base bb is 5 and the exponent yy is 3. Rewriting gives 53=x5^3 = x. Evaluating 535^3 yields 5×5×5=1255 \times 5 \times 5 = 125. Therefore, the correct value of xx is 125.

Adım Adım Çözüm

1
Apply the definition of a logarithm to rewrite the logarithmic equation in its equivalent exponential form.
53=x5^3 = x
By definition, logbx=y\log_b x = y is equivalent to by=xb^y = x, where bb is the base, yy is the exponent, and xx is the argument.
2
Evaluate the exponential expression 535^3 to solve for xx.
x=125x = 125
Cubing 5 means multiplying it by itself three times: 5×5×5=1255 \times 5 \times 5 = 125.

Anahtar Kavram

Definition of Logarithms
Soru 2039Soru

The table below shows some values of the functions ff and gg for several integer values of xx.

xxf(x)f(x)g(x)g(x)
2-23311
1-1442-2
001-133
112200
222-21-1
331122

What is the value of f(f(3))+g(g(1))f(f(3)) + g(g(-1))?

Cevabı ve açıklamayı göster

Cevap: 3

Cevap

The value of the expression is 33.
To evaluate f(f(3))+g(g(1))f(f(3)) + g(g(-1)), we start by evaluating the innermost expressions. Looking at the table for x=3x = 3, we find f(3)=1f(3) = 1. Looking at the table for x=1x = -1, we find g(1)=2g(-1) = -2. Substituting these values into the outer functions gives f(1)+g(2)f(1) + g(-2). Using the table again, we look up x=1x = 1 to find f(1)=2f(1) = 2, and look up x=2x = -2 to find g(2)=1g(-2) = 1. Adding these two results yields 2+1=32 + 1 = 3.

Adım Adım Çözüm

1
Find the inner function values from the given table.
f(3)=1f(3) = 1 and g(1)=2g(-1) = -2
Before evaluating the composite functions, we must find the outputs of the innermost functions.
2
Evaluate the outer functions using the results from the first step.
f(f(3))=f(1)=2f(f(3)) = f(1) = 2 and g(g(1))=g(2)=1g(g(-1)) = g(-2) = 1
Substitute the inner outputs into the outer functions and look up the new inputs in the table.
3
Add the two resulting values together.
2+1=32 + 1 = 3
Combine the two terms to find the total sum requested by the question.

Anahtar Kavram

Evaluating composite functions using tables of values
Tahmini Süre:1m 0s
Soru 2040Soru

A company sells two types of gift baskets: Standard and Premium. The sales at the company's North and South branches are represented by matrix SS:

S=[1281510]S = \begin{bmatrix} 12 & 8 \\ 15 & 10 \end{bmatrix}

where the rows represent the North and South branches, respectively, and the columns represent the number of Standard and Premium baskets sold, respectively. The cost of the items inside each basket is represented by matrix CC:

C=[x2430y]C = \begin{bmatrix} x & 24 \\ 30 & y \end{bmatrix}

where the rows represent Standard and Premium baskets, respectively, and the columns represent the cost of food items and the cost of gift items (in dollars), respectively. If the total food item cost at the North branch is 600600 and the total gift item cost at the South branch is 760760, what is the value of x+yx + y?

Cevabı ve açıklamayı göster

Cevap: 70

Cevap

The value of x+yx + y is 70.
To find the total costs, the sales matrix SS is multiplied by the unit cost matrix CC. The product matrix R=SCR = SC is a 2×22 \times 2 matrix where the entry in Row 1, Column 1 represents the total food cost at the North branch, and the entry in Row 2, Column 2 represents the total gift cost at the South branch. Setting up the equations 12x+240=60012x + 240 = 600 and 360+10y=760360 + 10y = 760 yields x=30x = 30 and y=40y = 40, which sum to 70.

Adım Adım Çözüm

1
Set up the matrix multiplication R=SCR = SC to represent the total costs.
R=[12x+240288+8y15x+300360+10y]R = \begin{bmatrix} 12x + 240 & 288 + 8y \\ 15x + 300 & 360 + 10y \end{bmatrix}
The product of the sales matrix and the unit cost matrix yields the total cost matrix, where rows represent the branches and columns represent the cost categories.
2
Identify the expression for the total food item cost at the North branch and solve for xx.
x=30x = 30
The total food item cost at the North branch is the entry in Row 1, Column 1 of the product matrix, which is 12x+8(30)=12x+24012x + 8(30) = 12x + 240. Setting this equal to 600600 gives 12x+240=60012x + 240 = 600, which simplifies to 12x=36012x = 360, so x=30x = 30.
3
Identify the expression for the total gift item cost at the South branch and solve for yy.
y=40y = 40
The total gift item cost at the South branch is the entry in Row 2, Column 2 of the product matrix, which is 15(24)+10y=360+10y15(24) + 10y = 360 + 10y. Setting this equal to 760760 gives 360+10y=760360 + 10y = 760, which simplifies to 10y=40010y = 400, so y=40y = 40.
4
Calculate the sum of the variables xx and yy.
x+y=70x + y = 70
Substitute x=30x = 30 and y=40y = 40 into the expression x+yx + y to find the final answer.

Anahtar Kavram

Matrix multiplication and translating real-world scenarios into matrix equations.
Tahmini Süre:3m 0s
ÖncekiSayfa 102 / 278Sonraki
Tüm alıştırma soruları — ACT | Examkin