Calculus

175 soru

Soru 41Soru

Given that y=3x1(x+2)2y = \frac{3x - 1}{(x + 2)^2}, what is the value of dydx\frac{dy}{dx} at x=1x = 1?

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Cevap: 527\frac{5}{27}

Cevap

The value of dydx\frac{dy}{dx} at x=1x = 1 is 527\frac{5}{27}.
Applying the quotient rule dydx=uvuvv2\frac{dy}{dx} = \frac{u'v - uv'}{v^2} with u=3x1u = 3x - 1 and v=(x+2)2v = (x + 2)^2 yields dydx=83x(x+2)3\frac{dy}{dx} = \frac{8 - 3x}{(x + 2)^3}. Substituting x=1x = 1 results in 83(1)(1+2)3=527\frac{8 - 3(1)}{(1 + 2)^3} = \frac{5}{27}.

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1
Identify the numerator u(x)u(x) and denominator v(x)v(x) for the quotient rule.
Let u=3x1u = 3x - 1 and v=(x+2)2v = (x + 2)^2.
The given function y=uvy = \frac{u}{v} requires the quotient rule dydx=uvuvv2\frac{dy}{dx} = \frac{u'v - uv'}{v^2}.
2
Differentiate u(x)u(x) and v(x)v(x) with respect to xx.
u=3u' = 3 and, using the chain rule, v=2(x+2)(1)=2(x+2)v' = 2(x + 2)(1) = 2(x + 2).
The derivative of the inner term (x+2)(x + 2) is 11, giving v=2(x+2)v' = 2(x + 2).
3
Substitute u,v,u,vu, v, u', v' into the quotient rule formula and simplify.
dydx=3(x+2)2(3x1)2(x+2)(x+2)4=(x+2)[3(x+2)2(3x1)](x+2)4=3x+66x+2(x+2)3=83x(x+2)3\frac{dy}{dx} = \frac{3(x + 2)^2 - (3x - 1) \cdot 2(x + 2)}{(x + 2)^4} = \frac{(x + 2)[3(x + 2) - 2(3x - 1)]}{(x + 2)^4} = \frac{3x + 6 - 6x + 2}{(x + 2)^3} = \frac{8 - 3x}{(x + 2)^3}.
Factoring out (x+2)(x + 2) simplifies the algebraic expression.
4
Evaluate the derivative at x=1x = 1.
dydxx=1=83(1)(1+2)3=533=527\frac{dy}{dx}\Big|_{x=1} = \frac{8 - 3(1)}{(1 + 2)^3} = \frac{5}{3^3} = \frac{5}{27}.
Substituting x=1x = 1 gives the final numerical derivative value.

Anahtar Kavram

Quotient and Chain Rules of Differentiation
Soru 42Soru

Given the function y=2x3(x2+1)2y = \frac{2x - 3}{(x^2 + 1)^2}, find the numerical value of dydx\frac{dy}{dx} at x=1x = 1.

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Cevap: 1

Cevap

The numerical value of dydx\frac{dy}{dx} at x=1x = 1 is 1.
Applying the quotient rule dydx=uvuvv2\frac{dy}{dx} = \frac{u'v - uv'}{v^2} alongside the chain rule for the denominator yields dydx=2(x2+1)2(2x3)4x(x2+1)(x2+1)4\frac{dy}{dx} = \frac{2(x^2 + 1)^2 - (2x - 3) \cdot 4x(x^2 + 1)}{(x^2 + 1)^4}. Substituting x=1x = 1 evaluates to 2(4)(1)(8)16=1616=1\frac{2(4) - (-1)(8)}{16} = \frac{16}{16} = 1.

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1
Identify the numerator and denominator functions
Let u(x)=2x3u(x) = 2x - 3 and v(x)=(x2+1)2v(x) = (x^2 + 1)^2.
The given function is structured as a quotient y=uvy = \frac{u}{v}, requiring the quotient rule.
2
Find the derivatives u(x)u'(x) and v(x)v'(x)
u(x)=2u'(x) = 2 and v(x)=2(x2+1)2x=4x(x2+1)v'(x) = 2(x^2 + 1) \cdot 2x = 4x(x^2 + 1).
Differentiating u(x)u(x) follows standard polynomial rules; v(x)v(x) requires the chain rule.
3
Evaluate u(1),u(1),v(1),u(1), u'(1), v(1), and v(1)v'(1) at x=1x = 1
u(1)=1u(1) = -1, u(1)=2u'(1) = 2, v(1)=4v(1) = 4, and v(1)=8v'(1) = 8.
Evaluating components before substitution simplifies the arithmetic.
4
Apply the quotient rule formula dydx=uvuvv2\frac{dy}{dx} = \frac{u'v - uv'}{v^2} at x=1x = 1
\frac{dy}{dx} = \frac{(2)(4) - (-1)(8)}{4^2} = \frac{8 + 8}{16} = 1.
Substitute the calculated component values into the quotient rule formula.

Anahtar Kavram

Quotient Rule and Chain Rule of Differentiation
Tahmini Süre:1m 30s
Soru 43Soru

Given the function y=x2+2x(3x1)2y = \frac{x^2 + 2x}{(3x - 1)^2}, what is the value of dydx\frac{dy}{dx} at x=1x = 1?

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Cevap: 54-\frac{5}{4}

Cevap

54-\frac{5}{4}
Applying the quotient rule dydx=vuuvv2\frac{dy}{dx} = \frac{v u' - u v'}{v^2} with u=x2+2xu = x^2 + 2x (u=2x+2u' = 2x + 2) and v=(3x1)2v = (3x - 1)^2 (v=6(3x1)v' = 6(3x - 1)) yields dydx=163616=54\frac{dy}{dx} = \frac{16 - 36}{16} = -\frac{5}{4} at x=1x = 1.

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1
Identify the numerator and denominator functions for the quotient rule y=uvy = \frac{u}{v}.
u=x2+2xu = x^2 + 2x and v=(3x1)2v = (3x - 1)^2.
The function is structured as a quotient of two algebraic expressions.
2
Differentiate uu and vv with respect to xx.
dudx=2x+2\frac{du}{dx} = 2x + 2 and dvdx=2(3x1)3=6(3x1)\frac{dv}{dx} = 2(3x - 1) \cdot 3 = 6(3x - 1).
Use the power rule for uu and the chain rule for vv.
3
Apply the quotient rule formula dydx=vdudxudvdxv2\frac{dy}{dx} = \frac{v \frac{du}{dx} - u \frac{dv}{dx}}{v^2}.
dydx=(3x1)2(2x+2)(x2+2x)6(3x1)(3x1)4\frac{dy}{dx} = \frac{(3x - 1)^2 (2x + 2) - (x^2 + 2x) \cdot 6(3x - 1)}{(3x - 1)^4}.
The quotient rule formula combines the expressions and their derivatives.
4
Substitute x=1x = 1 into the derivative expression and simplify.
dydx=(2)2(4)(3)6(2)(2)4=163616=2016=54\frac{dy}{dx} = \frac{(2)^2 (4) - (3) \cdot 6(2)}{(2)^4} = \frac{16 - 36}{16} = -\frac{20}{16} = -\frac{5}{4}.
Evaluating at x=1x = 1 yields the numerical derivative value.

Anahtar Kavram

Quotient Rule and Chain Rule of Differentiation
Soru 44Soru

What is the indefinite integral (3x25sin(5x)+2)dx\int (3x^2 - 5\sin(5x) + 2) \, dx?

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Cevap: x3+cos(5x)+2x+Cx^3 + \cos(5x) + 2x + C

Cevap

x3+cos(5x)+2x+Cx^3 + \cos(5x) + 2x + C
Integrating term-by-term yields 3x2dx=x3\int 3x^2 dx = x^3, 5sin(5x)dx=cos(5x)\int -5\sin(5x) dx = \cos(5x), and 2dx=2x\int 2 dx = 2x. Adding the arbitrary constant CC produces x3+cos(5x)+2x+Cx^3 + \cos(5x) + 2x + C.

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1
Integrate the polynomial term 3x23x^2 using the power rule xndx=xn+1n+1\int x^n dx = \frac{x^{n+1}}{n+1}
3x2dx=3x33=x3\int 3x^2 dx = 3 \cdot \frac{x^3}{3} = x^3
Applying the power rule for integration.
2
Integrate the trigonometric term 5sin(5x)-5\sin(5x) using sin(kx)dx=1kcos(kx)\int \sin(kx) dx = -\frac{1}{k}\cos(kx)
5sin(5x)dx=5(15cos(5x))=cos(5x)\int -5\sin(5x) dx = -5 \left(-\frac{1}{5}\cos(5x)\right) = \cos(5x)
Integration of the sine function reverses differentiation with a positive sign change for negative sine.
3
Integrate the constant term 22 and append the constant of integration CC
2dx=2x\int 2 dx = 2x, giving total antiderivative x3+cos(5x)+2x+Cx^3 + \cos(5x) + 2x + C
Indefinite integrals always require an arbitrary constant of integration CC.

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Indefinite Integration of Polynomial and Trigonometric Functions
Soru 45Soru

What is the x-coordinate of the maximum stationary point of the curve y=sinx+cosxy = \sin x + \cos x in the interval 0xπ0 \le x \le \pi?

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Cevap: π4\frac{\pi}{4}

Cevap

The x-coordinate of the maximum stationary point is π4\frac{\pi}{4}.
To find stationary points, we differentiate y=sinx+cosxy = \sin x + \cos x to get dydx=cosxsinx\frac{dy}{dx} = \cos x - \sin x. Setting dydx=0\frac{dy}{dx} = 0 gives sinx=cosx\sin x = \cos x, or tanx=1\tan x = 1. Within 0xπ0 \le x \le \pi, the solution is x=π4x = \frac{\pi}{4}. Evaluating the second derivative d2ydx2=sinxcosx\frac{d^2y}{dx^2} = -\sin x - \cos x at x=π4x = \frac{\pi}{4} yields 2<0-\sqrt{2} < 0, confirming a local maximum.

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1
Differentiate the function y=sinx+cosxy = \sin x + \cos x with respect to xx.
dydx=cosxsinx\frac{dy}{dx} = \cos x - \sin x
Stationary points occur where the first derivative dydx=0\frac{dy}{dx} = 0.
2
Set the first derivative to zero and solve for xx in the interval 0xπ0 \le x \le \pi.
\cos x - \sin x = 0 \implies \sin x = \cos x \implies \tan x = 1 \implies x = \frac{\pi}{4}
Dividing both sides by cosx\cos x gives tanx=1\tan x = 1, which has the solution x=π4x = \frac{\pi}{4} in the given domain.
3
Verify the nature of the stationary point using the second derivative test.
\frac{d^2y}{dx^2} = -\sin x - \cos x \implies \left.\frac{d^2y}{dx^2}\right|_{x=\frac{\pi}{4}} = -\frac{\sqrt{2}}{2} - \frac{\sqrt{2}}{2} = -\sqrt{2} < 0
A negative second derivative confirms that x=π4x = \frac{\pi}{4} is a local maximum point.

Anahtar Kavram

Finding stationary points and determining their nature using derivatives of trigonometric functions.
Soru 46Soru

Find the positive constant pp such that the value of the definite integral 0p(3x2+2x)dx\int_{0}^{p} (3x^2 + 2x) \, dx is equal to 1212.

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Cevap: 2

Cevap

The positive constant pp is equal to 22.
Evaluating the definite integral 0p(3x2+2x)dx\int_{0}^{p} (3x^2 + 2x) \, dx gives p3+p2p^3 + p^2. Setting this expression equal to 1212 forms the cubic equation p3+p212=0p^3 + p^2 - 12 = 0. Solving for the positive real solution yields p=2p = 2, since 23+22=8+4=122^3 + 2^2 = 8 + 4 = 12.

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1
Find the antiderivative of the integrand
\int (3x^2 + 2x) \, dx = x^3 + x^2 + C
Applying the power rule for integration xndx=xn+1n+1\int x^n dx = \frac{x^{n+1}}{n+1} term by term gives 3x33+2x22=x3+x2\frac{3x^3}{3} + \frac{2x^2}{2} = x^3 + x^2.
2
Evaluate the antiderivative at the limits 00 and pp
\left[ x^3 + x^2 \right]_0^p = (p^3 + p^2) - (0^3 + 0^2) = p^3 + p^2
Using the Fundamental Theorem of Calculus: substitute the upper limit pp and subtract the value at the lower limit 00.
3
Set up the polynomial equation using the given integral value
p^3 + p^2 = 12 \implies p^3 + p^2 - 12 = 0
The problem states that the definite integral equals 12.
4
Solve for the positive real value of pp
p = 2
Testing p=2p=2: 23+22=8+4=122^3 + 2^2 = 8 + 4 = 12. Factoring gives (p2)(p2+3p+6)=0(p-2)(p^2 + 3p + 6) = 0, where the quadratic factor has a negative discriminant 324(1)(6)=15<03^2 - 4(1)(6) = -15 < 0, making p=2p=2 the only real solution.

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Definite integration with an unknown limit of integration
Soru 47Soru

What is the value of the definite integral 0π3cos(2x)dx\int_{0}^{\frac{\pi}{3}} \cos(2x) \, dx?

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Cevap: 34\frac{\sqrt{3}}{4}

Cevap

34\frac{\sqrt{3}}{4}
The antiderivative of cos(2x)\cos(2x) is 12sin(2x)\frac{1}{2}\sin(2x). Substituting the limits gives 12sin(2π3)12sin(0)=12(32)0=34\frac{1}{2}\sin\left(\frac{2\pi}{3}\right) - \frac{1}{2}\sin(0) = \frac{1}{2}\left(\frac{\sqrt{3}}{2}\right) - 0 = \frac{\sqrt{3}}{4}, which is correct.

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1
Find the antiderivative of cos(2x)\cos(2x)
cos(2x)dx=12sin(2x)+C\int \cos(2x) \, dx = \frac{1}{2}\sin(2x) + C
Using standard trigonometric integration rules, cos(kx)dx=1ksin(kx)+C\int \cos(kx) \, dx = \frac{1}{k}\sin(kx) + C.
2
Substitute the upper limit x=π3x = \frac{\pi}{3} and lower limit x=0x = 0
[12sin(2x)]0π3=12sin(2π3)12sin(0)\left[\frac{1}{2}\sin(2x)\right]_{0}^{\frac{\pi}{3}} = \frac{1}{2}\sin\left(\frac{2\pi}{3}\right) - \frac{1}{2}\sin(0)
Apply the Fundamental Theorem of Calculus: abf(x)dx=F(b)F(a)\int_{a}^{b} f(x)dx = F(b) - F(a).
3
Evaluate the trigonometric values and simplify
12(32)0=34\frac{1}{2}\left(\frac{\sqrt{3}}{2}\right) - 0 = \frac{\sqrt{3}}{4}
sin(2π3)=sin(120)=32\sin\left(\frac{2\pi}{3}\right) = \sin(120^\circ) = \frac{\sqrt{3}}{2} and sin(0)=0\sin(0) = 0.

Anahtar Kavram

Definite Integration of Trigonometric Functions
Soru 48Soru

What is the value of the definite integral 12(4x33x2+2)dx\int_{1}^{2} (4x^3 - 3x^2 + 2) \, dx?

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Cevap: 10

Cevap

10
Integrating each term yields F(x)=x4x3+2xF(x) = x^4 - x^3 + 2x. Substituting the upper boundary gives F(2)=12F(2) = 12 and the lower boundary gives F(1)=2F(1) = 2. Calculating F(2)F(1)F(2) - F(1) gives 122=1012 - 2 = 10, which is the exact value of the definite integral.

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1
Find the indefinite antiderivative of the integrand 4x33x2+24x^3 - 3x^2 + 2.
F(x)=(4x33x2+2)dx=x4x3+2xF(x) = \int (4x^3 - 3x^2 + 2) \, dx = x^4 - x^3 + 2x
Apply the power rule of integration xndx=xn+1n+1\int x^n dx = \frac{x^{n+1}}{n+1} to each term.
2
Evaluate the antiderivative at the upper limit x=2x = 2.
F(2)=(2)4(2)3+2(2)=168+4=12F(2) = (2)^4 - (2)^3 + 2(2) = 16 - 8 + 4 = 12
Substitute x=2x = 2 into F(x)F(x).
3
Evaluate the antiderivative at the lower limit x=1x = 1.
F(1)=(1)4(1)3+2(1)=11+2=2F(1) = (1)^4 - (1)^3 + 2(1) = 1 - 1 + 2 = 2
Substitute x=1x = 1 into F(x)F(x).
4
Subtract the lower limit value from the upper limit value.
F(2)F(1)=122=10F(2) - F(1) = 12 - 2 = 10
Apply the Fundamental Theorem of Calculus: abf(x)dx=F(b)F(a)\int_{a}^{b} f(x) dx = F(b) - F(a).

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Definite Integration of Polynomial Functions
Tahmini Süre:1m 30s
Soru 49Soru

Find the value of the definite integral 12(x+1x2)dx\int_{1}^{2} \left(x + \frac{1}{x^2}\right) dx.

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Cevap: 2

Cevap

The value of the definite integral is 2.
Integrating x+x2x + x^{-2} gives x221x\frac{x^2}{2} - \frac{1}{x}. Evaluating from x=1x=1 to x=2x=2 yields (212)(121)=32(12)=2\left(2 - \frac{1}{2}\right) - \left(\frac{1}{2} - 1\right) = \frac{3}{2} - \left(-\frac{1}{2}\right) = 2.

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1
Find the antiderivative of f(x)=x+x2f(x) = x + x^{-2}
F(x)=x221x+CF(x) = \frac{x^2}{2} - \frac{1}{x} + C
Apply the power rule of integration xndx=xn+1n+1\int x^n dx = \frac{x^{n+1}}{n+1} for n1n \neq -1.
2
Evaluate F(x)F(x) at the upper boundary x=2x = 2
F(2)=22212=212=32F(2) = \frac{2^2}{2} - \frac{1}{2} = 2 - \frac{1}{2} = \frac{3}{2}
Substitute x=2x = 2 into the antiderivative.
3
Evaluate F(x)F(x) at the lower boundary x=1x = 1
F(1)=12211=121=12F(1) = \frac{1^2}{2} - \frac{1}{1} = \frac{1}{2} - 1 = -\frac{1}{2}
Substitute x=1x = 1 into the antiderivative.
4
Calculate F(2)F(1)F(2) - F(1)
32(12)=32+12=2\frac{3}{2} - \left(-\frac{1}{2}\right) = \frac{3}{2} + \frac{1}{2} = 2
Apply the Fundamental Theorem of Calculus: abf(x)dx=F(b)F(a)\int_{a}^{b} f(x) dx = F(b) - F(a).

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Definite Integration using the Power Rule
Soru 50Soru

What is the yy-intercept of the normal line to the curve y=2x1x+1y = \frac{2x - 1}{x + 1} at the point where the curve crosses the xx-axis?

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Cevap: 38\frac{3}{8}

Cevap

The yy-intercept of the normal line is 38\frac{3}{8}.
To find the yy-intercept of the normal line, set y=0y = 0 to find the point of contact on the xx-axis, which gives (12,0)\left(\frac{1}{2}, 0\right). Differentiating y=2x1x+1y = \frac{2x - 1}{x + 1} gives dydx=3(x+1)2\frac{dy}{dx} = \frac{3}{(x + 1)^2}. At x=12x = \frac{1}{2}, the tangent slope is 43\frac{4}{3}, making the normal slope 34-\frac{3}{4}. The equation of the normal line is y=34x+38y = -\frac{3}{4}x + \frac{3}{8}, so its yy-intercept is 38\frac{3}{8}.

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1
Find the point of intersection of the curve with the xx-axis
Set y=0    2x1x+1=0    2x1=0    x=12y = 0 \implies \frac{2x - 1}{x + 1} = 0 \implies 2x - 1 = 0 \implies x = \frac{1}{2}. The point is (12,0)\left(\frac{1}{2}, 0\right).
The normal line is drawn at the point where the curve crosses the xx-axis.
2
Differentiate y=2x1x+1y = \frac{2x - 1}{x + 1} using the quotient rule
\(\frac{dy}{dx} = \frac{2(x + 1) - (2x - 1)(1)}{(x + 1)^2} = \frac{2x + 2 - 2x + 1}{(x + 1)^2} = \frac{3}{(x + 1)^2}\)
The derivative provides the gradient function of the tangent line to the curve.
3
Evaluate the gradient of the tangent and normal lines at x=12x = \frac{1}{2}
Tangent gradient mt=3(12+1)2=394=43m_t = \frac{3}{\left(\frac{1}{2} + 1\right)^2} = \frac{3}{\frac{9}{4}} = \frac{4}{3}. Normal gradient mn=1mt=34m_n = -\frac{1}{m_t} = -\frac{3}{4}.
The normal line is perpendicular to the tangent line at the point of contact.
4
Determine the equation of the normal line and evaluate its yy-intercept
Using y0=34(x12)    y=34x+38y - 0 = -\frac{3}{4}\left(x - \frac{1}{2}\right) \implies y = -\frac{3}{4}x + \frac{3}{8}. Setting x=0x = 0 gives y=38y = \frac{3}{8}.
The yy-intercept is the value of yy when x=0x = 0 on the line.

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Tangents and Normals to Curves
Soru 51Soru

Using differentiation from first principles, evaluate the value of the derivative dydx=limh0f(x+h)f(x)h\frac{dy}{dx} = \lim_{h \to 0} \frac{f(x+h) - f(x)}{h} for the cubic function f(x)=2x39x2+12x5f(x) = 2x^3 - 9x^2 + 12x - 5 at the point x=3x = 3.

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Cevap: 12

Cevap

The derivative evaluated at x=3x = 3 is equal to 12.
Evaluating the definition of the derivative from first principles for f(x)=2x39x2+12x5f(x) = 2x^3 - 9x^2 + 12x - 5 yields limh0f(x+h)f(x)h=6x218x+12\lim_{h \to 0} \frac{f(x+h) - f(x)}{h} = 6x^2 - 18x + 12. Substituting x=3x = 3 gives 6(3)218(3)+12=5454+12=126(3)^2 - 18(3) + 12 = 54 - 54 + 12 = 12.

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1
Set up the difference quotient definition from first principles
f(x)=limh0f(x+h)f(x)hf'(x) = \lim_{h \to 0} \frac{f(x+h) - f(x)}{h}
Differentiation from first principles requires finding the limit of the average rate of change as the increment hh approaches zero.
2
Substitute (x+h)(x+h) into f(x)=2x39x2+12x5f(x) = 2x^3 - 9x^2 + 12x - 5 and expand
f(x+h)=2x3+6x2h+6xh2+2h39x218xh9h2+12x+12h5f(x+h) = 2x^3 + 6x^2h + 6xh^2 + 2h^3 - 9x^2 - 18xh - 9h^2 + 12x + 12h - 5
Expanding binomial terms (x+h)3(x+h)^3 and (x+h)2(x+h)^2 reveals all components involving hh.
3
Calculate f(x+h)f(x)f(x+h) - f(x) and factor out hh
f(x+h)f(x)=h(6x2+6xh+2h218x9h+12)f(x+h) - f(x) = h(6x^2 + 6xh + 2h^2 - 18x - 9h + 12)
Terms independent of hh cancel out completely, isolating hh as a common factor.
4
Divide by hh and evaluate the limit as h0h \to 0
f(x)=6x218x+12f'(x) = 6x^2 - 18x + 12
Canceling hh resolves the 00\frac{0}{0} indeterminate form, allowing direct substitution of h=0h=0.
5
Substitute x=3x = 3 into f(x)f'(x)
f(3)=6(3)218(3)+12=12f'(3) = 6(3)^2 - 18(3) + 12 = 12
Evaluating at x=3x = 3 gives the numerical value of the instantaneous rate of change at that specific point.

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Differentiation from First Principles
Soru 52Soru

Given the function y=(x2+1)32x3y = \frac{(x^2 + 1)^3}{2x - 3}, what is the numerical value of dydx\frac{dy}{dx} evaluated at x=2x = 2?

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Cevap: 50

Cevap

The numerical value of dydx\frac{dy}{dx} at x=2x = 2 is 50.
Applying the Quotient Rule dydx=uvuvv2\frac{dy}{dx} = \frac{u'v - uv'}{v^2} along with the Chain Rule to find u(x)=6x(x2+1)2u'(x) = 6x(x^2 + 1)^2, and evaluating all components at x=2x = 2 gives u(2)=125u(2) = 125, u(2)=300u'(2) = 300, v(2)=1v(2) = 1, and v(2)=2v'(2) = 2. Substituting these values yields (300)(1)(125)(2)12=50\frac{(300)(1) - (125)(2)}{1^2} = 50.

Adım Adım Çözüm

1
Set up the Quotient Rule components
u(x)=(x2+1)3u(x) = (x^2 + 1)^3 and v(x)=2x3v(x) = 2x - 3
The given expression is a quotient of two functions requiring dydx=uvuvv2\frac{dy}{dx} = \frac{u'v - uv'}{v^2}.
2
Differentiate u(x)u(x) using the Chain Rule and v(x)v(x) using basic power rules
u(x)=6x(x2+1)2u'(x) = 6x(x^2 + 1)^2 and v(x)=2v'(x) = 2
Differentiating the outer power 3 gives 3(x2+1)23(x^2 + 1)^2, and multiplying by the derivative of the inner function (2x)(2x) gives 6x(x2+1)26x(x^2 + 1)^2.
3
Evaluate u(2)u(2), u(2)u'(2), v(2)v(2), and v(2)v'(2)
u(2)=125u(2) = 125, u(2)=300u'(2) = 300, v(2)=1v(2) = 1, and v(2)=2v'(2) = 2
Substituting x=2x = 2 into each function and derivative simplifies calculation of the overall derivative.
4
Substitute values into the Quotient Rule formula
dydxx=2=(300)(1)(125)(2)(1)2=50\left.\frac{dy}{dx}\right|_{x=2} = \frac{(300)(1) - (125)(2)}{(1)^2} = 50
Evaluating u(2)v(2)u(2)v(2)[v(2)]2\frac{u'(2)v(2) - u(2)v'(2)}{[v(2)]^2} yields the exact numerical result.

Anahtar Kavram

Combined Application of Quotient Rule and Chain Rule
Soru 53Soru

What is the indefinite integral ((32x)(4x+1)+8cos(4x))dx\int \left( (3 - 2x)(4x + 1) + 8\cos(4x) \right) dx?

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Cevap: 83x3+5x2+3x+2sin(4x)+C-\frac{8}{3}x^3 + 5x^2 + 3x + 2\sin(4x) + C

Cevap

83x3+5x2+3x+2sin(4x)+C-\frac{8}{3}x^3 + 5x^2 + 3x + 2\sin(4x) + C
Expanding the product (32x)(4x+1)(3 - 2x)(4x + 1) gives 8x2+10x+3-8x^2 + 10x + 3. Integrating term-by-term yields 8x2dx=83x3\int -8x^2 dx = -\frac{8}{3}x^3, 10xdx=5x2\int 10x dx = 5x^2, 3dx=3x\int 3 dx = 3x, and 8cos(4x)dx=84sin(4x)=2sin(4x)\int 8\cos(4x) dx = \frac{8}{4}\sin(4x) = 2\sin(4x). Adding the integration constant CC gives the complete result 83x3+5x2+3x+2sin(4x)+C-\frac{8}{3}x^3 + 5x^2 + 3x + 2\sin(4x) + C.

Adım Adım Çözüm

1
Expand the polynomial product inside the integrand
(32x)(4x+1)=12x+38x22x=8x2+10x+3(3 - 2x)(4x + 1) = 12x + 3 - 8x^2 - 2x = -8x^2 + 10x + 3
Expanding the expression allows term-by-term integration using standard rules.
2
Rewrite the full integrand
(8x2+10x+3+8cos(4x))dx\int \left( -8x^2 + 10x + 3 + 8\cos(4x) \right) dx
Substitute the expanded polynomial back into the integral expression.
3
Integrate each term individually
8x2dx=83x3\int -8x^2 dx = -\frac{8}{3}x^3, 10xdx=5x2\int 10x dx = 5x^2, 3dx=3x\int 3 dx = 3x, 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 linear trigonometric rule cos(kx)dx=sin(kx)k\int \cos(kx) dx = \frac{\sin(kx)}{k}.
4
Combine terms and append the constant of integration
83x3+5x2+3x+2sin(4x)+C-\frac{8}{3}x^3 + 5x^2 + 3x + 2\sin(4x) + C
Indefinite integration requires adding an arbitrary constant CC.

Anahtar Kavram

Indefinite Integration of Polynomial and Trigonometric Functions
Tahmini Süre:2m 0s
Soru 54Soru

What is the equation of the normal line to the curve y=x33x+2y = x^3 - 3x + 2 at the point where x=2x = 2?

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Cevap: x+9y38=0x + 9y - 38 = 0

Cevap

The equation of the normal line is x+9y38=0x + 9y - 38 = 0.
Evaluating yy at x=2x = 2 gives the point (2,4)(2, 4). Differentiating y=x33x+2y = x^3 - 3x + 2 yields dydx=3x23\frac{dy}{dx} = 3x^2 - 3. At x=2x = 2, the tangent slope is mt=9m_t = 9, making the normal slope mn=1/9m_n = -1/9. Using the point-slope formula y4=1/9(x2)y - 4 = -1/9(x - 2) simplifies to x+9y38=0x + 9y - 38 = 0.

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1
Find the yy-coordinate at x=2x = 2
y=(2)33(2)+2=86+2=4y = (2)^3 - 3(2) + 2 = 8 - 6 + 2 = 4. The point on the curve is (2,4)(2, 4).
The point of tangency/normal line intersection must be determined on the curve.
2
Calculate the derivative dydx\frac{dy}{dx} to find the slope of the tangent line
dydx=3x23\frac{dy}{dx} = 3x^2 - 3. At x=2x = 2, dydx=3(2)23=123=9\frac{dy}{dx} = 3(2)^2 - 3 = 12 - 3 = 9.
The derivative evaluated at x=2x = 2 gives the gradient of the tangent line.
3
Find the slope of the normal line
mn=1mt=19m_n = -\frac{1}{m_t} = -\frac{1}{9}.
The normal line is perpendicular to the tangent line, so its slope is the negative reciprocal of the tangent slope.
4
Use the point-slope form to find the equation of the normal line
y4=19(x2)    9(y4)=(x2)    9y36=x+2    x+9y38=0y - 4 = -\frac{1}{9}(x - 2) \implies 9(y - 4) = -(x - 2) \implies 9y - 36 = -x + 2 \implies x + 9y - 38 = 0.
Substituting point (2,4)(2, 4) and slope 1/9-1/9 into yy1=mn(xx1)y - y_1 = m_n(x - x_1) yields the standard line equation.

Anahtar Kavram

The slope of the normal line to a curve y=f(x)y = f(x) at (x1,y1)(x_1, y_1) is mn=1f(x1)m_n = -\frac{1}{f'(x_1)}.
Soru 55Soru
What is the numerical value of the limit limx4x4x+53\lim_{x \to 4} \frac{x - 4}{\sqrt{x + 5} - 3}?
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Cevap: 66

Cevap

The value of the limit is 66.
Multiplying both the numerator and the denominator by the conjugate of the denominator (x+5+3)(\sqrt{x + 5} + 3) allows the factor (x4)(x - 4) to cancel out, leaving x+5+3\sqrt{x + 5} + 3. Evaluating this expression as x4x \to 4 yields 3+3=63 + 3 = 6.

Adım Adım Çözüm

1
Check for direct substitution.
Substituting x=4x = 4 yields 444+53=033=00\frac{4 - 4}{\sqrt{4 + 5} - 3} = \frac{0}{3 - 3} = \frac{0}{0}, which is an indeterminate form.
Direct substitution gives 00\frac{0}{0}, requiring algebraic simplification such as rationalization.
2
Rationalize the denominator by multiplying the numerator and denominator by the conjugate (x+5+3)(\sqrt{x + 5} + 3).
limx4(x4)(x+5+3)(x+53)(x+5+3)=limx4(x4)(x+5+3)(x+5)9\lim_{x \to 4} \frac{(x - 4)(\sqrt{x + 5} + 3)}{(\sqrt{x + 5} - 3)(\sqrt{x + 5} + 3)} = \lim_{x \to 4} \frac{(x - 4)(\sqrt{x + 5} + 3)}{(x + 5) - 9}
Using the difference of squares formula (ab)(a+b)=a2b2(a - b)(a + b) = a^2 - b^2 eliminates the square root in the denominator.
3
Simplify the denominator and cancel out the common factor (x4)(x - 4).
limx4(x4)(x+5+3)x4=limx4(x+5+3)\lim_{x \to 4} \frac{(x - 4)(\sqrt{x + 5} + 3)}{x - 4} = \lim_{x \to 4} (\sqrt{x + 5} + 3)
Since x4x \neq 4 when evaluating the limit, the indeterminate factor (x4)(x - 4) cancels out.
4
Substitute x=4x = 4 into the simplified expression.
4+5+3=9+3=3+3=6\sqrt{4 + 5} + 3 = \sqrt{9} + 3 = 3 + 3 = 6
Evaluates the limit after removing the zero-denominator condition.

Anahtar Kavram

Limits of indeterminate forms 00\frac{0}{0} involving radicals (Rationalization Technique)
Tahmini Süre:1m 30s
Soru 56Soru

If y=ln(e3xcosx)y = \ln(e^{3x} \cos x), what is dydx\frac{dy}{dx}?

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Cevap: 3tanx3 - \tan x

Cevap

3tanx3 - \tan x
Applying the product rule for logarithms converts y=ln(e3xcosx)y = \ln(e^{3x} \cos x) into y=3x+ln(cosx)y = 3x + \ln(\cos x). Differentiating 3x3x yields 33, and differentiating ln(cosx)\ln(\cos x) by chain rule yields sinxcosx=tanx\frac{-\sin x}{\cos x} = -\tan x. Combining these gives 3tanx3 - \tan x.

Adım Adım Çözüm

1
Simplify the logarithmic function using log laws
y=ln(e3x)+ln(cosx)=3x+ln(cosx)y = \ln(e^{3x}) + \ln(\cos x) = 3x + \ln(\cos x)
Splitting the logarithm of a product simplifies the differentiation process.
2
Differentiate each term with respect to xx
\frac{dy}{dx} = \frac{d}{dx}(3x) + \frac{d}{dx}(\ln(\cos x)) = 3 + \frac{1}{\cos x} \cdot (-\sin x)
The derivative of 3x3x is 33, and applying the chain rule to ln(u)\ln(u) gives 1ududx\frac{1}{u} \cdot \frac{du}{dx} where u=cosxu = \cos x.
3
Simplify the trigonometric ratio
\frac{dy}{dx} = 3 - \frac{\sin x}{\cos x} = 3 - \tan x
Replacing sinxcosx\frac{\sin x}{\cos x} with tanx\tan x yields the simplified final derivative.

Anahtar Kavram

Differentiation of Logarithmic and Trigonometric Functions via Chain Rule and Log Laws
Soru 57Soru
Evaluate the algebraic limit:
limx4x2x216\lim_{x \to 4} \frac{\sqrt{x} - 2}{x^2 - 16}
What is the exact value of this limit?
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Cevap: 132\frac{1}{32}

Cevap

The exact value of the limit is 132\frac{1}{32}.
The limit presents an indeterminate form 00\frac{0}{0} at x=4x = 4. Factoring x216x^2 - 16 into (x2)(x+2)(x+4)(\sqrt{x} - 2)(\sqrt{x} + 2)(x + 4) allows the factor (x2)(\sqrt{x} - 2) to be cancelled from both the numerator and denominator. Substituting x=4x = 4 into the simplified expression 1(x+2)(x+4)\frac{1}{(\sqrt{x} + 2)(x + 4)} yields 1(2+2)(4+4)=132\frac{1}{(2+2)(4+4)} = \frac{1}{32}.

Adım Adım Çözüm

1
Identify the form of the limit by direct substitution.
Substituting x=4x = 4 into 424216\frac{\sqrt{4} - 2}{4^2 - 16} gives 00\frac{0}{0}, which is an indeterminate form.
Direct substitution yields 00\frac{0}{0}, requiring algebraic simplification.
2
Factor the denominator x216x^2 - 16.
x216=(x4)(x+4)x^2 - 16 = (x - 4)(x + 4)
Use the difference of two squares identity a2b2=(ab)(a+b)a^2 - b^2 = (a - b)(a + b).
3
Factor (x4)(x - 4) as a difference of squares involving square roots.
x4=(x)222=(x2)(x+2)x - 4 = (\sqrt{x})^2 - 2^2 = (\sqrt{x} - 2)(\sqrt{x} + 2)
This exposes the vanishing factor (x2)(\sqrt{x} - 2) in the denominator.
4
Cancel the common factor (x2)(\sqrt{x} - 2) and evaluate the limit.
limx4x2(x2)(x+2)(x+4)=limx41(x+2)(x+4)=1(4+2)(4+4)=14×8=132\lim_{x \to 4} \frac{\sqrt{x} - 2}{(\sqrt{x} - 2)(\sqrt{x} + 2)(x + 4)} = \lim_{x \to 4} \frac{1}{(\sqrt{x} + 2)(x + 4)} = \frac{1}{(\sqrt{4} + 2)(4 + 4)} = \frac{1}{4 \times 8} = \frac{1}{32}
Cancelling the factor removing the 00\frac{0}{0} condition allows direct evaluation.

Anahtar Kavram

Resolution of indeterminate limits of the form 0/0 using algebraic factorization and conjugate radical identities.
Tahmini Süre:2m 0s
Soru 58Soru

A curve has the equation y=13x32x2+3x+1y = \frac{1}{3}x^3 - 2x^2 + 3x + 1. What is the positive xx-coordinate of the point on the curve where the tangent line is parallel to the line y=8x5y = 8x - 5?

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Cevap: 5

Cevap

The positive xx-coordinate of the point where the tangent is parallel to the line is 55.
The gradient of the line y=8x5y = 8x - 5 is 88. Differentiating y=13x32x2+3x+1y = \frac{1}{3}x^3 - 2x^2 + 3x + 1 gives dydx=x24x+3\frac{dy}{dx} = x^2 - 4x + 3. Setting dydx=8\frac{dy}{dx} = 8 leads to x24x5=0x^2 - 4x - 5 = 0, which factors as (x5)(x+1)=0(x - 5)(x + 1) = 0. The solutions are x=5x = 5 and x=1x = -1. Selecting the positive value gives x=5x = 5.

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1
Find the gradient (slope) of the given straight line.
The line equation is in slope-intercept form y=mx+cy = mx + c, where the slope m=8m = 8.
Parallel lines have equal slopes, so the gradient of the tangent to the curve must equal 8.
2
Differentiate the curve equation to find the gradient function dydx\frac{dy}{dx}.
dydx=ddx(13x32x2+3x+1)=x24x+3\frac{dy}{dx} = \frac{d}{dx}\left(\frac{1}{3}x^3 - 2x^2 + 3x + 1\right) = x^2 - 4x + 3.
The first derivative of a curve represents the gradient of the tangent at any point xx.
3
Equate the derivative to the slope of the line and solve for xx.
x24x+3=8    x24x5=0    (x5)(x+1)=0x^2 - 4x + 3 = 8 \implies x^2 - 4x - 5 = 0 \implies (x - 5)(x + 1) = 0. The roots are x=5x = 5 and x=1x = -1.
Solving the quadratic equation gives all xx-values where the tangent line has a slope of 8.
4
Select the positive xx-coordinate as requested.
x=5x = 5.
The question specifically asks for the positive value among the solutions.

Anahtar Kavram

Finding points on a curve where the tangent is parallel to a given line
Soru 59Soru

If y=(2x1)3(x2+1)2y = (2x - 1)^3(x^2 + 1)^2, find the numerical value of dydx\frac{dy}{dx} at x=1x = 1.

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Cevap: 32

Cevap

The numerical value of dydx\frac{dy}{dx} evaluated at x=1x = 1 is 3232.
Using the product rule together with the chain rule for composite functions, we find u(x)=6(2x1)2u'(x) = 6(2x - 1)^2 and v(x)=4x(x2+1)v'(x) = 4x(x^2 + 1). Evaluating at x=1x = 1 gives u(1)=1u(1)=1, u(1)=6u'(1)=6, v(1)=4v(1)=4, and v(1)=8v'(1)=8. Calculating dydx=u(1)v(1)+u(1)v(1)=6(4)+1(8)=32\frac{dy}{dx} = u'(1)v(1) + u(1)v'(1) = 6(4) + 1(8) = 32.

Adım Adım Çözüm

1
Set up the product rule for y=u(x)v(x)y = u(x)v(x)
u(x)=(2x1)3u(x) = (2x - 1)^3 and v(x)=(x2+1)2v(x) = (x^2 + 1)^2
The given function is a product of two composite expressions.
2
Differentiate u(x)u(x) using the chain rule
u(x)=3(2x1)22=6(2x1)2u'(x) = 3(2x - 1)^2 \cdot 2 = 6(2x - 1)^2
Differentiating the outer power function and multiplying by the derivative of the inner function 2x12x - 1.
3
Differentiate v(x)v(x) using the chain rule
v(x)=2(x2+1)2x=4x(x2+1)v'(x) = 2(x^2 + 1) \cdot 2x = 4x(x^2 + 1)
Differentiating the outer power function and multiplying by the derivative of the inner function x2+1x^2 + 1.
4
Apply the product rule formula dydx=u(x)v(x)+u(x)v(x)\frac{dy}{dx} = u'(x)v(x) + u(x)v'(x) and evaluate at x=1x = 1
u(1)=1u(1) = 1, u(1)=6u'(1) = 6, v(1)=4v(1) = 4, v(1)=8v'(1) = 8, giving dydxx=1=(6)(4)+(1)(8)=32\frac{dy}{dx}\Big|_{x=1} = (6)(4) + (1)(8) = 32
Substituting x=1x = 1 into each individual term simplifies the arithmetic before combining.

Anahtar Kavram

Combined application of the Product Rule and Chain Rule
Soru 60Soru

Evaluate the definite integral 02(3x2+4)dx\int_{0}^{2} (3x^2 + 4) \, dx.

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Cevap: 16

Cevap

The value of the definite integral is 1616.
Integrating 3x2+43x^2 + 4 with respect to xx gives the antiderivative F(x)=x3+4xF(x) = x^3 + 4x. Evaluating this antiderivative at the upper limit x=2x = 2 yields 23+4(2)=162^3 + 4(2) = 16, and at the lower limit x=0x = 0 yields 03+4(0)=00^3 + 4(0) = 0. Subtracting the lower boundary value from the upper boundary value gives 160=1616 - 0 = 16.

Adım Adım Çözüm

1
Integrate the polynomial term by term
\int (3x^2 + 4) dx = x^3 + 4x
Apply the power rule of integration \int x^n dx = \frac{x^{n+1}}{n+1} and \int k dx = kx.
2
Apply the fundamental theorem of calculus with limits 0 and 2
[x^3 + 4x]_0^2 = (2^3 + 4(2)) - (0^3 + 4(0)) = 16 - 0 = 16
Evaluate F(b) - F(a) where F(x) is the antiderivative.

Anahtar Kavram

Definite Integral Evaluation using the Fundamental Theorem of Calculus
ÖncekiSayfa 3 / 9Sonraki
Calculus Alıştırma Soruları — JAMB UTME — Sayfa 3 | Examkin