Calculus

175 soru

Soru 121Soru

If y=(x+1)3x2+1y = \frac{(x + 1)^3}{x^2 + 1}, find the value of dydx\frac{dy}{dx} at x=1x = 1.

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Cevap: 2

Cevap

The numerical value of the derivative at x=1x = 1 is 2.
To find dydx\frac{dy}{dx} at x=1x = 1 for y=(x+1)3x2+1y = \frac{(x + 1)^3}{x^2 + 1}, we use the quotient rule dydx=vdudxudvdxv2\frac{dy}{dx} = \frac{v \frac{du}{dx} - u \frac{dv}{dx}}{v^2}. Setting u=(x+1)3u = (x + 1)^3 gives dudx=3(x+1)2\frac{du}{dx} = 3(x + 1)^2, and setting v=x2+1v = x^2 + 1 gives dvdx=2x\frac{dv}{dx} = 2x. At x=1x = 1, u=8u = 8, dudx=12\frac{du}{dx} = 12, v=2v = 2, and dvdx=2\frac{dv}{dx} = 2. Substituting into the quotient formula gives (2)(12)(8)(2)22=24164=2\frac{(2)(12) - (8)(2)}{2^2} = \frac{24 - 16}{4} = 2.

Adım Adım Çözüm

1
Identify the components of the quotient rule
Let u(x)=(x+1)3u(x) = (x + 1)^3 and v(x)=x2+1v(x) = x^2 + 1.
The given function is a quotient of two functions of xx.
2
Differentiate the numerator using the chain rule and the denominator using standard rules
u(x)=3(x+1)2u'(x) = 3(x + 1)^2 and v(x)=2xv'(x) = 2x.
The chain rule states that ddx[g(x)n]=ng(x)n1g(x)\frac{d}{dx}[g(x)^n] = n \cdot g(x)^{n-1} \cdot g'(x).
3
Evaluate all function components at x=1x = 1
u(1)=8u(1) = 8, u(1)=12u'(1) = 12, v(1)=2v(1) = 2, and v(1)=2v'(1) = 2.
Substituting x=1x = 1 simplifies the calculation before applying the full quotient expression.
4
Apply the quotient rule formula to calculate the final derivative value
dydxx=1=v(1)u(1)u(1)v(1)[v(1)]2=(2)(12)(8)(2)22=24164=2\frac{dy}{dx}\Big|_{x=1} = \frac{v(1)u'(1) - u(1)v'(1)}{[v(1)]^2} = \frac{(2)(12) - (8)(2)}{2^2} = \frac{24 - 16}{4} = 2.
Substituting the numerical values yields the final result.

Anahtar Kavram

Combining the Quotient Rule and Chain Rule for differentiation
Soru 122Soru

A curve is defined by the equation y=4x+9xy = 4x + \frac{9}{x} for x>0x > 0. What is the yy-value at the minimum stationary point of the curve?

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Cevap: 12

Cevap

The yy-value at the minimum stationary point is 12.
To find the minimum value of y=4x+9xy = 4x + \frac{9}{x} for x>0x > 0, set the first derivative dydx=49x2\frac{dy}{dx} = 4 - \frac{9}{x^2} equal to 00, yielding x=1.5x = 1.5. The second derivative d2ydx2=18x3\frac{d^2y}{dx^2} = \frac{18}{x^3} is positive at x=1.5x = 1.5, confirming a minimum stationary point. Evaluating the original equation at x=1.5x = 1.5 gives y=4(1.5)+91.5=6+6=12y = 4(1.5) + \frac{9}{1.5} = 6 + 6 = 12.

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1
Differentiate the given function y=4x+9x1y = 4x + 9x^{-1} with respect to xx.
\frac{dy}{dx} = 4 - 9x^{-2} = 4 - \frac{9}{x^2}
Stationary points occur where the gradient (first derivative) equals zero.
2
Set the first derivative to zero and solve for xx given the domain constraint x>0x > 0.
4 - \frac{9}{x^2} = 0 \implies 4x^2 = 9 \implies x^2 = \frac{9}{4} \implies x = \frac{3}{2} = 1.5
Solving dydx=0\frac{dy}{dx} = 0 yields the xx-coordinate of the turning point.
3
Evaluate the second derivative to confirm the turning point is a local minimum.
\frac{d^2y}{dx^2} = \frac{18}{x^3}. \text{ At } x = 1.5, \frac{d^2y}{dx^2} = \frac{18}{3.375} = 5.333 > 0
A positive second derivative indicates that the stationary point is a local minimum.
4
Substitute x=1.5x = 1.5 back into the original equation y=4x+9xy = 4x + \frac{9}{x} to find the corresponding yy-value.
y = 4(1.5) + \frac{9}{1.5} = 6 + 6 = 12
The question asks for the yy-value of the curve at the minimum stationary point.

Anahtar Kavram

Stationary Points, Maxima, and Minima
Tahmini Süre:2m 0s
Soru 123Soru

If y=x23x+1y = x^2 \sqrt{3x + 1}, what is the value of dydx\frac{dy}{dx} evaluated at x=1x = 1?

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Cevap: 194\frac{19}{4}

Cevap

The numerical value of dydx\frac{dy}{dx} at x=1x = 1 is 194\frac{19}{4}.
Applying the product rule to y=x23x+1y = x^2 \sqrt{3x + 1} gives dydx=x2ddx(3x+1)+3x+1ddx(x2)\frac{dy}{dx} = x^2 \cdot \frac{d}{dx}(\sqrt{3x + 1}) + \sqrt{3x + 1} \cdot \frac{d}{dx}(x^2). By the chain rule, ddx(3x+1)=323x+1\frac{d}{dx}(\sqrt{3x + 1}) = \frac{3}{2\sqrt{3x + 1}}. Substituting x=1x = 1 into dydx=3x223x+1+2x3x+1\frac{dy}{dx} = \frac{3x^2}{2\sqrt{3x + 1}} + 2x\sqrt{3x + 1} gives 34+4=194\frac{3}{4} + 4 = \frac{19}{4}. Thus, the option equal to 194\frac{19}{4} is correct.

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1
Identify the main differentiation rule required and split the function into two components.
Let u=x2u = x^2 and v=(3x+1)1/2v = (3x + 1)^{1/2}, so y=uvy = u \cdot v.
The function is a product of x2x^2 and a composite function 3x+1\sqrt{3x + 1}.
2
Differentiate uu with respect to xx, and use the chain rule to differentiate vv with respect to xx.
dudx=2x\frac{du}{dx} = 2x and dvdx=12(3x+1)1/23=323x+1\frac{dv}{dx} = \frac{1}{2}(3x + 1)^{-1/2} \cdot 3 = \frac{3}{2\sqrt{3x + 1}}.
The chain rule requires multiplying the derivative of the outer square root function by the derivative of the inner linear function 3x+13x + 1.
3
Apply the product rule formula dydx=udvdx+vdudx\frac{dy}{dx} = u \frac{dv}{dx} + v \frac{du}{dx}.
dydx=x2(323x+1)+3x+1(2x)\frac{dy}{dx} = x^2 \left( \frac{3}{2\sqrt{3x + 1}} \right) + \sqrt{3x + 1} (2x).
The derivative of a product uvuv is uv+vuu v' + v u'.
4
Substitute x=1x = 1 into the derivative expression.
dydxx=1=(1)2(323(1)+1)+3(1)+12(1)=1(34)+22=34+4=194\frac{dy}{dx}\Big|_{x=1} = (1)^2 \left( \frac{3}{2\sqrt{3(1) + 1}} \right) + \sqrt{3(1) + 1} \cdot 2(1) = 1 \cdot \left( \frac{3}{4} \right) + 2 \cdot 2 = \frac{3}{4} + 4 = \frac{19}{4}.
Evaluating at x=1x = 1 requires simplifying 4=2\sqrt{4} = 2 and combining fractions.

Anahtar Kavram

Combining Product Rule and Chain Rule for Differentiation
Soru 124Soru

Find the area of the region bounded by the curve y=3x2y = 3x^2, the xx-axis, and the vertical lines x=1x = 1 and x=3x = 3.

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Cevap: 26

Cevap

The area of the bounded region is 26 square units.
The area under y=3x2y = 3x^2 from x=1x = 1 to x=3x = 3 is calculated using the definite integral 133x2dx=[x3]13=3313=271=26\int_{1}^{3} 3x^2 \, dx = [x^3]_{1}^{3} = 3^3 - 1^3 = 27 - 1 = 26 square units.

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1
Set up the definite integral representing the bounded area.
A=133x2dxA = \int_{1}^{3} 3x^2 \, dx
The area under a non-negative curve y=f(x)y = f(x) from x=ax = a to x=bx = b above the xx-axis is given by the definite integral abf(x)dx\int_{a}^{b} f(x) \, dx.
2
Determine the antiderivative of 3x23x^2.
3x2dx=3x33=x3\int 3x^2 \, dx = 3 \cdot \frac{x^3}{3} = x^3
Applying the power rule of integration xndx=xn+1n+1\int x^n \, dx = \frac{x^{n+1}}{n+1} gives x3x^3.
3
Evaluate the definite integral using the fundamental theorem of calculus.
[x3]13=3313=271=26[x^3]_{1}^{3} = 3^3 - 1^3 = 27 - 1 = 26
Substitute the upper limit x=3x = 3 and subtract the value of the function evaluated at the lower limit x=1x = 1.

Anahtar Kavram

Area under a curve using definite integration
Soru 125Soru

Using differentiation from first principles, what is the value of the derivative of the function f(x)=x2+2xf(x) = x^2 + 2x at the point where x=3x = 3?

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Cevap: 8

Cevap

The derivative of f(x)=x2+2xf(x) = x^2 + 2x evaluated at x=3x = 3 is 8.
Applying first principles to f(x)=x2+2xf(x) = x^2 + 2x yields f(x)=limh0(x+h)2+2(x+h)(x2+2x)h=limh0(2x+h+2)=2x+2f'(x) = \lim_{h \to 0} \frac{(x+h)^2 + 2(x+h) - (x^2 + 2x)}{h} = \lim_{h \to 0} (2x + h + 2) = 2x + 2. Evaluating this derivative at x=3x = 3 gives 2(3)+2=82(3) + 2 = 8.

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1
Apply the definition of differentiation from first principles
f(x)=limh0f(x+h)f(x)hf'(x) = \lim_{h \to 0} \frac{f(x+h) - f(x)}{h}
First principles uses the limit of the difference quotient to compute the instantaneous rate of change.
2
Substitute f(x)=x2+2xf(x) = x^2 + 2x into the difference quotient
[(x+h)2+2(x+h)](x2+2x)h=2xh+h2+2hh\frac{[(x+h)^2 + 2(x+h)] - (x^2 + 2x)}{h} = \frac{2xh + h^2 + 2h}{h}
Expanding terms allows cancellation of non-hh terms in the numerator.
3
Simplify the fraction by dividing by hh
2x+h+22x + h + 2
Dividing out hh removes the indeterminate form 00\frac{0}{0}.
4
Evaluate the limit as h0h \to 0 and substitute x=3x = 3
f(3)=2(3)+2=8f'(3) = 2(3) + 2 = 8
Setting h=0h = 0 yields the derivative function f(x)=2x+2f'(x) = 2x + 2, which evaluates to 8 at x=3x = 3.

Anahtar Kavram

Differentiation from First Principles
Soru 126Soru

The line 3xy+k=03x - y + k = 0 is a normal to the curve y=x+2x1y = \frac{x + 2}{x - 1} at a point PP located in the first quadrant. What is the value of the constant kk?

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Cevap: -10

Cevap

The value of the constant kk is 10-10.
Differentiating y=x+2x1y = \frac{x + 2}{x - 1} yields dydx=3(x1)2\frac{dy}{dx} = \frac{-3}{(x - 1)^2}. The gradient of the normal line is mN=1dy/dx=(x1)23m_N = -\frac{1}{dy/dx} = \frac{(x - 1)^2}{3}. Equating mNm_N to the gradient of 3xy+k=03x - y + k = 0 (which is 33) gives (x1)23=3    (x1)2=9\frac{(x - 1)^2}{3} = 3 \implies (x - 1)^2 = 9. Solving gives x=4x = 4 or x=2x = -2. Since point PP lies in the first quadrant, x=4x = 4, which gives y=4+241=2y = \frac{4 + 2}{4 - 1} = 2. Substituting (4,2)(4, 2) into 3xy+k=03x - y + k = 0 gives 3(4)2+k=03(4) - 2 + k = 0, so k=10k = -10.

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1
Differentiate the curve equation to find the tangent gradient function.
Using the quotient rule on y=x+2x1y = \frac{x + 2}{x - 1}, dydx=1(x1)1(x+2)(x1)2=3(x1)2\frac{dy}{dx} = \frac{1(x - 1) - 1(x + 2)}{(x - 1)^2} = \frac{-3}{(x - 1)^2}.
The derivative gives the gradient of the tangent line to the curve at any point xx.
2
Determine the gradient function for the normal line.
The normal gradient is mN=1dy/dx=(x1)23m_N = -\frac{1}{dy/dx} = \frac{(x - 1)^2}{3}.
The normal line is perpendicular to the tangent line, so its gradient is the negative reciprocal of dydx\frac{dy}{dx}.
3
Equate the normal gradient to the gradient of the given line and solve for xx.
The line 3xy+k=03x - y + k = 0 has gradient 33. Setting (x1)23=3    (x1)2=9    x1=±3\frac{(x - 1)^2}{3} = 3 \implies (x - 1)^2 = 9 \implies x - 1 = \pm 3, giving x=4x = 4 or x=2x = -2.
The normal line at point PP must be parallel to (and thus have the same gradient as) the given line 3xy+k=03x - y + k = 0.
4
Select the coordinate corresponding to the first quadrant and calculate the yy-coordinate.
Since PP lies in the first quadrant (x>0,y>0x > 0, y > 0), x=4x = 4. Substituting x=4x = 4 into the curve equation gives y=4+241=2y = \frac{4 + 2}{4 - 1} = 2. Thus, P=(4,2)P = (4, 2).
The problem specifies that point PP is located in the first quadrant.
5
Substitute point P(4,2)P(4, 2) into the line equation to solve for kk.
Substituting x=4x = 4 and y=2y = 2 into 3xy+k=03x - y + k = 0 yields 3(4)2+k=0    10+k=0    k=103(4) - 2 + k = 0 \implies 10 + k = 0 \implies k = -10.
Point PP lies on the normal line, so its coordinates must satisfy the line equation.

Anahtar Kavram

The normal line to a curve at a point PP is perpendicular to the tangent line at PP, with gradient mnormal=1dy/dxm_{\text{normal}} = -\frac{1}{dy/dx}. A point PP on the curve must satisfy both the curve equation and the normal line equation.
Soru 127Soru

What is the value of the definite integral 04(x+1)dx\int_{0}^{4} (x + 1) \, dx?

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Cevap: 12

Cevap

The value of the definite integral is 12.
Integrating x+1x + 1 yields x22+x\frac{x^2}{2} + x. Substituting the upper limit x=4x = 4 gives 422+4=8+4=12\frac{4^2}{2} + 4 = 8 + 4 = 12. Substituting the lower limit x=0x = 0 gives 00. Calculating 12012 - 0 gives the final answer of 12.

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1
Find the antiderivative of the integrand f(x)=x+1f(x) = x + 1.
(x+1)dx=x22+x+C\int (x + 1) \, dx = \frac{x^2}{2} + x + C
Apply the power rule of integration xndx=xn+1n+1\int x^n \, dx = \frac{x^{n+1}}{n+1} to x1x^1 and 1=x01 = x^0.
2
Evaluate the antiderivative at the upper bound x=4x = 4 and lower bound x=0x = 0.
F(4)=422+4=162+4=12F(4) = \frac{4^2}{2} + 4 = \frac{16}{2} + 4 = 12, and F(0)=022+0=0F(0) = \frac{0^2}{2} + 0 = 0
Substitute the bounds into the antiderivative expression F(x)=x22+xF(x) = \frac{x^2}{2} + x.
3
Apply the Fundamental Theorem of Calculus F(b)F(a)F(b) - F(a).
F(4)F(0)=120=12F(4) - F(0) = 12 - 0 = 12
Subtract the lower bound result from the upper bound result.

Anahtar Kavram

Evaluation of definite integrals of simple linear polynomials

Alternatif Yöntem

The integral 04(x+1)dx\int_{0}^{4} (x + 1) \, dx represents the area of a trapezoid under y=x+1y = x + 1 from x=0x = 0 to x=4x = 4. The parallel vertical sides are h1=1h_1 = 1 and h2=5h_2 = 5, with width b=4b = 4. Using the area formula for a trapezoid: Area=1+52×4=3×4=12\text{Area} = \frac{1+5}{2} \times 4 = 3 \times 4 = 12.
Tahmini Süre:45s
Soru 128Soru

What is the value of the definite integral 0π6cos(3x)dx\int_{0}^{\frac{\pi}{6}} \cos(3x) \, dx?

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Cevap: 13\frac{1}{3}

Cevap

The value of the definite integral is 13\frac{1}{3}.
The antiderivative of cos(3x)\cos(3x) is 13sin(3x)\frac{1}{3}\sin(3x). Substituting the upper boundary x=π6x = \frac{\pi}{6} yields 13sin(π2)=13\frac{1}{3}\sin\left(\frac{\pi}{2}\right) = \frac{1}{3}, and substituting the lower boundary x=0x = 0 yields 00. Subtracting the lower bound evaluation from the upper bound evaluation gives 13\frac{1}{3}.

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1
Find the indefinite integral of cos(3x)\cos(3x)
cos(3x)dx=13sin(3x)+C\int \cos(3x) \, dx = \frac{1}{3}\sin(3x) + C
Using the standard integration rule cos(kx)dx=1ksin(kx)+C\int \cos(kx) \, dx = \frac{1}{k}\sin(kx) + C.
2
Apply the upper limit of integration x=π6x = \frac{\pi}{6}
\frac{1}{3}\sin\left(3 \cdot \frac{\pi}{6}\right) = \frac{1}{3}\sin\left(\frac{\pi}{2}\right) = \frac{1}{3}(1) = \frac{1}{3}
Substituting the upper limit into the antiderivative.
3
Apply the lower limit of integration x=0x = 0 and subtract
\frac{1}{3} - \frac{1}{3}\sin(0) = \frac{1}{3} - 0 = \frac{1}{3}
Evaluating the antiderivative at the limits according to the Fundamental Theorem of Calculus.

Anahtar Kavram

Definite Integration of Trigonometric Functions
Tahmini Süre:1m 30s
Soru 129Soru
What is the numerical value of the limit limx04+x4xx\lim_{x \to 0} \frac{\sqrt{4 + x} - \sqrt{4 - x}}{x}?
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Cevap: 12\frac{1}{2}

Cevap

The numerical value of the limit is \(\frac{1}{2}\).
Rationalizing the numerator by multiplying with its conjugate gives \(\frac{2x}{x(\sqrt{4+x} + \sqrt{4-x})}\). Canceling \(x\) yields \(\frac{2}{\sqrt{4+x} + \sqrt{4-x}}\), which evaluates to \(\frac{2}{4} = \frac{1}{2}\) as \(x \to 0\).

Adım Adım Çözüm

1
Identify the indeterminate form
Substituting \(x = 0\) directly yields \(\frac{\sqrt{4} - \sqrt{4}}{0} = \frac{0}{0}\), which is an indeterminate form requiring rationalization.
Direct evaluation cannot give the true limit value when an indeterminate form is encountered.
2
Rationalize the numerator
Multiply the numerator and denominator by the conjugate \(\sqrt{4 + x} + \sqrt{4 - x}\):
(4+x4x)(4+x+4x)x(4+x+4x)=(4+x)(4x)x(4+x+4x)\frac{(\sqrt{4 + x} - \sqrt{4 - x})(\sqrt{4 + x} + \sqrt{4 - x})}{x(\sqrt{4 + x} + \sqrt{4 - x})} = \frac{(4 + x) - (4 - x)}{x(\sqrt{4 + x} + \sqrt{4 - x})}
The difference of squares identity \((a - b)(a + b) = a^2 - b^2\) eliminates the radical signs in the numerator.
3
Simplify the numerator and cancel common terms
\(\frac{4 + x - 4 + x}{x(\sqrt{4 + x} + \sqrt{4 - x})} = \frac{2x}{x(\sqrt{4 + x} + \sqrt{4 - x})} = \frac{2}{\sqrt{4 + x} + \sqrt{4 - x}}\)
Canceling the common factor \(x\) eliminates the zero-causing term in the denominator.
4
Evaluate the simplified limit as \(x \to 0\)
\(\frac{2}{\sqrt{4 + 0} + \sqrt{4 - 0}} = \frac{2}{2 + 2} = \frac{2}{4} = \frac{1}{2}\)
Direct substitution is now valid since the expression is continuous at \(x = 0\).

Anahtar Kavram

Evaluation of algebraic limits of indeterminate form 0/0 using radical rationalization.
Soru 130Soru

If y=(6x5sin(x))dxy = \int (6x - 5\sin(x)) \, dx and y=12y = 12 when x=0x = 0, what is the value of the constant of integration CC?

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Cevap: 7

Cevap

7
Integrating 6x5sin(x)6x - 5\sin(x) yields 3x2+5cos(x)+C3x^2 + 5\cos(x) + C. Substituting x=0x = 0 and y=12y = 12 gives 12=3(0)2+5(1)+C=5+C12 = 3(0)^2 + 5(1) + C = 5 + C, which gives C=7C = 7.

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1
Integrate each term of 6x5sin(x)6x - 5\sin(x) with respect to xx
y=3x2+5cos(x)+Cy = 3x^2 + 5\cos(x) + C
The integral of 6x6x is 3x23x^2, and the integral of 5sin(x)-5\sin(x) is +5cos(x)+5\cos(x).
2
Substitute the initial conditions x=0x = 0 and y=12y = 12 to calculate CC
12=3(0)2+5cos(0)+C    12=5+C    C=712 = 3(0)^2 + 5\cos(0) + C \implies 12 = 5 + C \implies C = 7
Since cos(0)=1\cos(0) = 1, the right-hand side reduces to 5+C5 + C.

Anahtar Kavram

Indefinite Integration and Initial Value Evaluation
Soru 131Soru

A normal line is drawn to the curve y=x2+3x1y = \frac{x^2 + 3}{x - 1} at the point where x=2x = 2. Calculate the xx-intercept of this normal line.

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Cevap: -19

Cevap

The x-intercept of the normal line is -19.
Substituting x=2x = 2 into the curve function gives y=7y = 7. Differentiating via the quotient rule yields dydx=x22x3(x1)2\frac{dy}{dx} = \frac{x^2 - 2x - 3}{(x - 1)^2}, which equals 3-3 at x=2x = 2. The perpendicular slope of the normal line is 13\frac{1}{3}. Constructing the line equation through (2,7)(2, 7) gives x3y+19=0x - 3y + 19 = 0. Setting y=0y = 0 produces x=19x = -19.

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1
Find the point of contact by substituting x=2x = 2 into the curve equation
y=22+321=71=7y = \frac{2^2 + 3}{2 - 1} = \frac{7}{1} = 7, so the point is (2,7)(2, 7)
The line is drawn at x=2x = 2, so we need the full coordinate pair (x1,y1)(x_1, y_1)
2
Differentiate the curve y=x2+3x1y = \frac{x^2 + 3}{x - 1} using the quotient rule
\frac{dy}{dx} = \frac{(x - 1)(2x) - (x^2 + 3)(1)}{(x - 1)^2} = \frac{x^2 - 2x - 3}{(x - 1)^2}
The derivative gives the gradient function of the curve
3
Evaluate the tangent slope mtm_t at x=2x = 2
m_t = \frac{2^2 - 2(2) - 3}{(2 - 1)^2} = \frac{-3}{1} = -3
Evaluating the derivative yields the gradient of the tangent at the point
4
Determine the slope of the normal line mnm_n
m_n = -\frac{1}{m_t} = -\frac{1}{-3} = \frac{1}{3}
Normal lines are perpendicular to tangent lines, so mnmt=1m_n \cdot m_t = -1
5
Formulate the equation of the normal line passing through (2,7)(2, 7)
y - 7 = \frac{1}{3}(x - 2) \implies 3y - 21 = x - 2 \implies x - 3y + 19 = 0
Use the point-slope form yy1=m(xx1)y - y_1 = m(x - x_1)
6
Find the xx-intercept by setting y=0y = 0
x - 3(0) + 19 = 0 \implies x = -19
The xx-intercept occurs where the line crosses the xx-axis (y=0y = 0)

Anahtar Kavram

Finding the equation and x-intercept of a normal line to a curve
Tahmini Süre:2m 0s
Soru 132Soru

What is the value of the definite integral 13(3x22x)dx\int_{1}^{3} (3x^2 - 2x) \, dx?

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Cevap: 1818

Cevap

18
Integrating 3x22x3x^2 - 2x gives the antiderivative F(x)=x3x2F(x) = x^3 - x^2. Evaluating F(3)F(1)F(3) - F(1) gives (279)(11)=180=18(27 - 9) - (1 - 1) = 18 - 0 = 18.

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1
Find the indefinite integral of the function
\int (3x^2 - 2x) \, dx = x^3 - x^2
Apply the power rule of integration to each term: \int 3x^2 dx = x^3 and \int 2x dx = x^2.
2
Evaluate the antiderivative at the upper limit x = 3
(3)^3 - (3)^2 = 27 - 9 = 18
Substitute the upper limit into the antiderivative.
3
Evaluate the antiderivative at the lower limit x = 1
(1)^3 - (1)^2 = 1 - 1 = 0
Substitute the lower limit into the antiderivative.
4
Subtract the lower limit evaluation from the upper limit evaluation
18 - 0 = 18
By the Fundamental Theorem of Calculus, \int_{a}^{b} f(x) dx = F(b) - F(a).

Anahtar Kavram

Fundamental Theorem of Calculus for Definite Polynomial Integrals
Tahmini Süre:1m 0s
Soru 133Soru

Given that 1a(3x22x)dx=48\int_{1}^{a} (3x^2 - 2x) \, dx = 48, where a>1a > 1 is a constant, find the value of aa.

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Cevap: 4

Cevap

The value of the constant upper limit is 4.
Integrating 3x22x3x^2 - 2x yields x3x2x^3 - x^2. Applying limits from 11 to aa gives (a3a2)(11)=a3a2(a^3 - a^2) - (1 - 1) = a^3 - a^2. Setting a3a2=48a^3 - a^2 = 48, solving for a>1a > 1 gives a=4a = 4 because 4342=6416=484^3 - 4^2 = 64 - 16 = 48.

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1
Integrate the polynomial function with respect to xx
(3x22x)dx=x3x2+C\int (3x^2 - 2x) \, dx = x^3 - x^2 + C
Using the power rule of integration xndx=xn+1n+1\int x^n \, dx = \frac{x^{n+1}}{n+1} for each term.
2
Evaluate the antiderivative between the upper limit aa and lower limit 11
[x3x2]1a=(a3a2)(1312)=a3a2[x^3 - x^2]_1^a = (a^3 - a^2) - (1^3 - 1^2) = a^3 - a^2
By the Fundamental Theorem of Calculus, bcf(x)dx=F(c)F(b)\int_{b}^{c} f(x)dx = F(c) - F(b).
3
Equate the expression to the given total integral value and solve for aa
a3a2=48    a=4a^3 - a^2 = 48 \implies a = 4
Substituting a=4a=4 yields 4342=6416=484^3 - 4^2 = 64 - 16 = 48, which satisfies the equation.

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Definite Integrals with Unknown Limits
Soru 134Soru

By evaluating the limit of the difference quotient limh0f(x+h)f(x)h\lim_{h \to 0} \frac{f(x+h) - f(x)}{h}, determine the value of the derivative of the function f(x)=2x24x+5f(x) = 2x^2 - 4x + 5 at the point where x=3x = 3.

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Cevap: 8

Cevap

The value of the derivative of f(x)=2x24x+5f(x) = 2x^2 - 4x + 5 at x=3x = 3 is 8.
Applying first principles, f(x+h)f(x)=4xh+2h24hf(x+h) - f(x) = 4xh + 2h^2 - 4h. Dividing by hh gives 4x+2h44x + 2h - 4. Taking the limit as h0h \to 0 produces f(x)=4x4f'(x) = 4x - 4. Substituting x=3x = 3 yields 4(3)4=84(3) - 4 = 8.

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1
Substitute (x+h)(x+h) into the function f(x)=2x24x+5f(x) = 2x^2 - 4x + 5 and expand
f(x+h)=2(x2+2xh+h2)4x4h+5=2x2+4xh+2h24x4h+5f(x+h) = 2(x^2 + 2xh + h^2) - 4x - 4h + 5 = 2x^2 + 4xh + 2h^2 - 4x - 4h + 5
Apply algebraic expansion to determine the value of the function at x+hx+h.
2
Form the difference f(x+h)f(x)f(x+h) - f(x)
f(x+h)f(x)=4xh+2h24hf(x+h) - f(x) = 4xh + 2h^2 - 4h
Subtract the original function terms to leave only terms containing hh.
3
Divide the difference by hh
\frac{f(x+h) - f(x)}{h} = 4x + 2h - 4
Simplify the difference quotient prior to taking the limit.
4
Compute the limit as h0h \to 0
f(x)=4x4f'(x) = 4x - 4
Taking the limit yields the general derivative function f(x)f'(x).
5
Evaluate f(x)f'(x) at x=3x = 3
f(3)=4(3)4=8f'(3) = 4(3) - 4 = 8
Substitute x=3x = 3 to find the numerical rate of change at the given point.

Anahtar Kavram

Differentiation from First Principles
Soru 135Soru

If y=ln(cos(3x))y = \ln(\cos(3x)), what is dydx\frac{dy}{dx}?

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Cevap: 3tan(3x)-3\tan(3x)

Cevap

3tan(3x)-3\tan(3x)
Differentiating y=ln(cos(3x))y = \ln(\cos(3x)) requires using the chain rule twice: first for ln(u)\ln(u), giving 1cos(3x)\frac{1}{\cos(3x)}, and then for cos(3x)\cos(3x), giving 3sin(3x)-3\sin(3x). Multiplying these results yields 3sin(3x)cos(3x)\frac{-3\sin(3x)}{\cos(3x)}, which simplifies to 3tan(3x)-3\tan(3x).

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1
Apply the chain rule formula for differentiating logarithmic functions ddx[ln(u)]=1ududx\frac{d}{dx}[\ln(u)] = \frac{1}{u}\frac{du}{dx}
dydx=1cos(3x)ddx(cos(3x))\frac{dy}{dx} = \frac{1}{\cos(3x)} \cdot \frac{d}{dx}(\cos(3x))
The outer function is ln(u)\ln(u) where u=cos(3x)u = \cos(3x).
2
Differentiate the inner trigonometric function cos(3x)\cos(3x)
ddx(cos(3x))=3sin(3x)\frac{d}{dx}(\cos(3x)) = -3\sin(3x)
By the chain rule, ddx[cos(kx)]=ksin(kx)\frac{d}{dx}[\cos(kx)] = -k\sin(kx).
3
Multiply the terms and simplify using trigonometric identities
dydx=3sin(3x)cos(3x)=3tan(3x)\frac{dy}{dx} = \frac{-3\sin(3x)}{\cos(3x)} = -3\tan(3x)
Using the identity sin(θ)cos(θ)=tan(θ)\frac{\sin(\theta)}{\cos(\theta)} = \tan(\theta), the derivative simplifies to 3tan(3x)-3\tan(3x).

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Differentiation of Logarithmic and Trigonometric Functions via Chain Rule
Tahmini Süre:1m 30s
Soru 136Soru

Find the indefinite integral (3x(x2)+8cos(4x))dx\int \left( 3x(x - 2) + 8\cos(4x) \right) dx.

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Cevap: x33x2+2sin(4x)+Cx^3 - 3x^2 + 2\sin(4x) + C

Cevap

x33x2+2sin(4x)+Cx^3 - 3x^2 + 2\sin(4x) + C
Expanding 3x(x2)3x(x - 2) yields 3x26x3x^2 - 6x. Integrating 3x23x^2 gives x3x^3, integrating 6x-6x yields 3x2-3x^2, and integrating 8cos(4x)8\cos(4x) yields 2sin(4x)2\sin(4x). Adding the arbitrary constant CC produces x33x2+2sin(4x)+Cx^3 - 3x^2 + 2\sin(4x) + C.

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1
Expand the algebraic term inside the integrand.
3x(x2)=3x26x3x(x - 2) = 3x^2 - 6x, expressing the integral as (3x26x+8cos(4x))dx\int (3x^2 - 6x + 8\cos(4x)) dx.
Expanding the product converts the term into standard polynomial form suitable for integration.
2
Integrate each component term using basic integration rules.
3x2dx=x3\int 3x^2 dx = x^3, 6xdx=3x2\int -6x dx = -3x^2, and 8cos(4x)dx=8sin(4x)4=2sin(4x)\int 8\cos(4x) dx = 8 \cdot \frac{\sin(4x)}{4} = 2\sin(4x).
Apply the power rule xndx=xn+1n+1\int x^n dx = \frac{x^{n+1}}{n+1} and trigonometric rule cos(kx)dx=sin(kx)k\int \cos(kx) dx = \frac{\sin(kx)}{k}.
3
Combine terms and attach the constant of integration.
x33x2+2sin(4x)+Cx^3 - 3x^2 + 2\sin(4x) + C
An indefinite integral requires an arbitrary constant CC to represent the full set of antiderivatives.

Anahtar Kavram

Indefinite Integration of Polynomial and Trigonometric Functions
Soru 137Soru

Evaluate the definite integral 03(x2+2)dx\int_{0}^{3} (x^2 + 2) \, dx.

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Cevap: 15

Cevap

The value of the definite integral is 15.
Integrating x2+2x^2 + 2 with respect to xx yields [x33+2x]03\left[\frac{x^3}{3} + 2x\right]_{0}^{3}. Substituting the upper bound x=3x = 3 gives 273+6=15\frac{27}{3} + 6 = 15. Substituting the lower bound x=0x = 0 gives 00. The net value is 150=1515 - 0 = 15.

Adım Adım Çözüm

1
Find the antiderivative of x2+2x^2 + 2
x33+2x\frac{x^3}{3} + 2x
Apply the power rule of integration to each term.
2
Substitute the upper limit x=3x = 3
15
\frac{3^3}{3} + 2(3) = 9 + 6 = 15
3
Substitute the lower limit x=0x = 0
0
033+2(0)=0\frac{0^3}{3} + 2(0) = 0
4
Compute the difference between upper and lower limit values
15
15 - 0 = 15

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Definite Integration of Polynomial Functions
Tahmini Süre:45s
Soru 138Soru

If y=extanx+ln(2x+1)y = e^{-x} \tan x + \ln(2x + 1), find the value of dydx\frac{dy}{dx} at x=0x = 0.

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Cevap: 3

Cevap

The value of dydx\frac{dy}{dx} at x=0x = 0 is 3.
Applying the product rule to extanxe^{-x}\tan x gives extanx+exsec2x-e^{-x}\tan x + e^{-x}\sec^2 x, and applying the chain rule to ln(2x+1)\ln(2x+1) gives 22x+1\frac{2}{2x+1}. Evaluating dydx=extanx+exsec2x+22x+1\frac{dy}{dx} = -e^{-x}\tan x + e^{-x}\sec^2 x + \frac{2}{2x+1} at x=0x = 0 yields e0(0)+e0(1)+21=3-e^0(0) + e^0(1) + \frac{2}{1} = 3.

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1
Differentiate u(x)=extanxu(x) = e^{-x} \tan x using the product rule.
\frac{du}{dx} = -e^{-x} \tan x + e^{-x} \sec^2 x
The derivative of exe^{-x} is ex-e^{-x} and the derivative of tanx\tan x is \sec^2 x.
2
Differentiate v(x)=ln(2x+1)v(x) = \ln(2x + 1) using the chain rule.
dvdx=22x+1\frac{dv}{dx} = \frac{2}{2x + 1}
The derivative of ln(g(x))\ln(g(x)) is g(x)g(x)\frac{g'(x)}{g(x)}, where g(x)=2x+1g(x) = 2x + 1 and g(x)=2g'(x) = 2.
3
Sum the derivatives to find the complete expression for dydx\frac{dy}{dx}.
\frac{dy}{dx} = -e^{-x} \tan x + e^{-x} \sec^2 x + \frac{2}{2x + 1}
The derivative of a sum is equal to the sum of the derivatives.
4
Evaluate the derivative at x=0x = 0.
\frac{dy}{dx}\Big|_{x=0} = -e^0(0) + e^0(1)^2 + \frac{2}{1} = 3
Since tan(0)=0\tan(0) = 0, e0=1e^0 = 1, and sec(0)=1\sec(0) = 1, substituting x=0x = 0 simplifies the derivative to 0+1+2=30 + 1 + 2 = 3.

Anahtar Kavram

Differentiation of Transcendental Functions (Product and Chain Rules)
Soru 139Soru

What is the value of the definite integral 04xdx\int_{0}^{4} \sqrt{x} \, dx?

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Cevap: 163\frac{16}{3}

Cevap

163\frac{16}{3}
Applying the power rule to x1/2x^{1/2} gives 23x3/2\frac{2}{3}x^{3/2}. Substituting the upper limit x=4x = 4 yields 23(4)3/2=23(8)=163\frac{2}{3}(4)^{3/2} = \frac{2}{3}(8) = \frac{16}{3}, and substituting the lower limit x=0x = 0 yields 0. Subtracting the lower limit result from the upper limit result gives 163\frac{16}{3}.

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1
Express the integrand with a fractional exponent
x=x1/2\sqrt{x} = x^{1/2}
Rewriting the square root as a fractional exponent allows the application of the power rule of integration.
2
Find the antiderivative using the power rule of integration
x1/2dx=x1/2+11/2+1=x3/23/2=23x3/2\int x^{1/2} \, dx = \frac{x^{1/2 + 1}}{1/2 + 1} = \frac{x^{3/2}}{3/2} = \frac{2}{3}x^{3/2}
The power rule states that xndx=xn+1n+1\int x^n \, dx = \frac{x^{n+1}}{n+1} for n1n \neq -1.
3
Evaluate the antiderivative at the limits 4 and 0
[23x3/2]04=23(4)3/223(0)3/2=23(8)0=163\left[ \frac{2}{3}x^{3/2} \right]_{0}^{4} = \frac{2}{3}(4)^{3/2} - \frac{2}{3}(0)^{3/2} = \frac{2}{3}(8) - 0 = \frac{16}{3}
By the Fundamental Theorem of Calculus, evaluate F(b)F(a)F(b) - F(a).

Anahtar Kavram

Definite Integration using the Power Rule
Soru 140Soru

Find the total area of the region bounded by the curve y=3x26xy = 3x^2 - 6x, the xx-axis, and the vertical lines x=0x = 0 and x=3x = 3.

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Cevap: 8

Cevap

The total area bounded by the curve and the x-axis between x = 0 and x = 3 is 8 square units.
To find the total geometric area bounded by a curve and the x-axis, we must split the integral at any x-intercepts within the domain. For y=3x26xy = 3x^2 - 6x, the x-intercepts are x=0x = 0 and x=2x = 2. Between x=0x = 0 and x=2x = 2, the curve lies below the x-axis, giving an area magnitude of 44. Between x=2x = 2 and x=3x = 3, the curve lies above the x-axis, giving an area magnitude of 44. Summing these positive magnitudes gives a total area of 88.

Adım Adım Çözüm

1
Find the roots of the curve y=3x26xy = 3x^2 - 6x within the given interval [0,3][0, 3].
Setting 3x26x=03x^2 - 6x = 0 yields 3x(x2)=03x(x - 2) = 0, giving x=0x = 0 and x=2x = 2.
Roots inside the integration boundaries indicate where the curve crosses the x-axis, changing the sign of yy.
2
Determine the position of the curve relative to the x-axis on each sub-interval.
On [0,2][0, 2], y0y \le 0 (below the x-axis). On [2,3][2, 3], y0y \ge 0 (above the x-axis).
Geometric area must be non-negative, so regions below the x-axis require integrating y-y or taking the absolute value of the integral.
3
Evaluate the area A1A_1 for the region below the x-axis from x=0x = 0 to x=2x = 2.
A1=02(6x3x2)dx=[3x2x3]02=(3(4)8)0=4A_1 = \int_{0}^{2} (6x - 3x^2) \, dx = \left[ 3x^2 - x^3 \right]_{0}^{2} = (3(4) - 8) - 0 = 4.
Integrating y=6x3x2-y = 6x - 3x^2 yields the positive magnitude of the area below the x-axis.
4
Evaluate the area A2A_2 for the region above the x-axis from x=2x = 2 to x=3x = 3.
A2=23(3x26x)dx=[x33x2]23=(333(32))(233(22))=0(4)=4A_2 = \int_{2}^{3} (3x^2 - 6x) \, dx = \left[ x^3 - 3x^2 \right]_{2}^{3} = (3^3 - 3(3^2)) - (2^3 - 3(2^2)) = 0 - (-4) = 4.
Direct integration of yy on [2,3][2, 3] gives the area above the x-axis.
5
Combine the areas of both sub-regions.
Total Area =A1+A2=4+4=8= A_1 + A_2 = 4 + 4 = 8.
The total geometric area is the sum of the magnitudes of the areas of all separate bounded regions.

Anahtar Kavram

Calculating area under curves crossing the x-axis by splitting definite integrals at real roots
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