Mathematics
Differentiation and Derivatives
55 Questions
Differentiation involves finding the rate of change of functions using established mathematical rules. Topics include the chain rule, quotient rule, and calculating partial derivatives for multivariable equations. Mastery of these mathematical calculations is heavily tested in undergraduate entrance and competitive exams.
Chain rule derivativesQuotient rule applicationPartial derivatives calculationDirectional derivative vectorsLogarithmic function derivatives
Differentiation and Derivatives Questions
Derivative of ${ \log { x } }^{ \cos { x } }$ with respect to $x$ is
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${ \log { x } }^{ \cos { x } }\left[ \cfrac { \cos { x } }{ x\log { x } } -\sin { x } \log { \left( \log { x } \right) } \right] \quad $
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${ \log { x } }^{ \cos { x } }\left[ \cfrac { \cos { x } }{ x\log { x } } -\cos { x } \log { \left( \log { x } \right) } \right] \quad $
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${ \log { x } }^{ \sin { x } }\left[ \cfrac { \sin { x } }{ x\log { x } } -\sin { x } \log { \left( \log { x } \right) } \right] \quad $
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None of these
D
Correct answer
Explanation
Let $y=\log x^{\cos x}$
$\Rightarrow \ y=(\cos x)(\log x)$
$\therefore \dfrac {dy}{dx}=(\cos x) \left (\dfrac {1}{x}\right)+(-\sin x)(\log x)$
$=\dfrac {\cos x}{x}-\sin x\log x$
On differentiating an identity function, we get?
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Signum function
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Sinc function
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Constant function
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None
C
Correct answer
Explanation
Derivative of an Identity function gives a Constant function
$\dfrac{d(cx)}{dx} = c$
Where $c$ is a constant.
What is the derivative of (sin(x)) with respect to (x)?
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\(cos(x)\)
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\(sec(x)\)
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\(-sin(x)\)
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\(cosec(x)\)
A
Correct answer
Explanation
The derivative of (sin(x)) with respect to (x) is (cos(x)).
What is the exterior derivative of a differential form?
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The gradient of the differential form
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The divergence of the differential form
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The curl of the differential form
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The Laplacian of the differential form
Correct answer
Explanation
The exterior derivative of a differential form is a new differential form that measures the boundary of the form.
What is the purpose of using numerical differentiation in applications?
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Estimating the slope of a function at a given point
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Finding the roots of polynomials
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Solving differential equations
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Approximating integrals
A
Correct answer
Explanation
Numerical differentiation is used to approximate the derivative of a function at a given point using numerical methods, which is useful when the analytical derivative is difficult or impossible to obtain.
What is the derivative of the function (f(x) = x^3 + 2x^2 - 3x + 4)?
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3x^2 + 4x - 3
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3x^2 + 4x + 3
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3x^2 - 4x - 3
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3x^2 - 4x + 3
A
Correct answer
Explanation
The derivative of a function (f(x)) is given by the limit (\lim_{h \to 0} \frac{f(x+h) - f(x)}{h}). Applying this limit to the function (f(x) = x^3 + 2x^2 - 3x + 4), we get: (\lim_{h \to 0} \frac{(x+h)^3 + 2(x+h)^2 - 3(x+h) + 4 - (x^3 + 2x^2 - 3x + 4)}{h}) = (\lim_{h \to 0} \frac{x^3 + 3x^2h + 3xh^2 + h^3 + 2x^2 + 4xh + 2h^2 - 3x - 3h + 4 - x^3 - 2x^2 + 3x - 4}{h}) = (\lim_{h \to 0} \frac{3x^2h + 3xh^2 + h^3 + 4xh + 2h^2 - 3h}{h}) = (\lim_{h \to 0} \frac{h(3x^2 + 3xh + h^2 + 4x + 2h - 3)}{h}) = (\lim_{h \to 0} (3x^2 + 3xh + h^2 + 4x + 2h - 3)) = (3x^2 + 4x - 3). Therefore, the derivative of the function (f(x) = x^3 + 2x^2 - 3x + 4) is (3x^2 + 4x - 3).
What is the method of differences?
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A method for finding the derivative of a function
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A method for finding the integral of a function
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A method for finding the limit of a function
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A method for finding the power series expansion of a function
D
Correct answer
Explanation
The method of differences is a method for finding the power series expansion of a function.
What is the derivative of the function f(x) = x^3 - 2x^2 + 3x - 4?
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3x^2 - 4x + 3
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3x^2 - 2x + 3
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3x^2 - 4x + 1
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3x^2 - 2x + 1
A
Correct answer
Explanation
The derivative of a function f(x) is given by the formula f'(x) = lim_(h->0) [f(x+h) - f(x)] / h. Substituting f(x) = x^3 - 2x^2 + 3x - 4, we get f'(x) = lim_(h->0) [(x+h)^3 - 2(x+h)^2 + 3(x+h) - 4 - (x^3 - 2x^2 + 3x - 4)] / h = lim_(h->0) [x^3 + 3x^2h + 3xh^2 + h^3 - 2x^2 - 4xh - 2h^2 + 3x + 3h - 4 - x^3 + 2x^2 - 3x + 4] / h = lim_(h->0) [3x^2h + 3xh^2 + h^3 - 4xh - 2h^2 + 3h] / h = lim_(h->0) [3x^2 + 3xh + h^2 - 4x - 2h + 3] = 3x^2 - 4x + 3.
What is the derivative of the function f(x) = x^3 - 2x^2 + 3x - 4?
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3x^2 - 4x + 3
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3x^2 - 4x + 1
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3x^2 - 2x + 3
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3x^2 - 2x + 1
A
Correct answer
Explanation
The derivative of a function f(x) is given by the formula f'(x) = lim_(h->0) [f(x+h) - f(x)] / h. Substituting the values of f(x), we get f'(x) = lim_(h->0) [(x+h)^3 - 2(x+h)^2 + 3(x+h) - 4 - (x^3 - 2x^2 + 3x - 4)] / h. Simplifying this equation, we get f'(x) = 3x^2 - 4x + 3.
What is the name of the theorem that states that the derivative of an inverse function is equal to the reciprocal of the derivative of the original function?
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Inverse function theorem
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Chain rule
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Mean value theorem
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Cauchy's mean value theorem
A
Correct answer
Explanation
The inverse function theorem states that the derivative of an inverse function is equal to the reciprocal of the derivative of the original function.
What is the name of the theorem that states that the derivative of a logarithmic function is equal to the reciprocal of the function?
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Logarithmic differentiation theorem
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Chain rule
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Mean value theorem
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Cauchy's mean value theorem
A
Correct answer
Explanation
The logarithmic differentiation theorem states that the derivative of a logarithmic function is equal to the reciprocal of the function.
What is the name of the theorem that states that the derivative of an exponential function is equal to the function itself?
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Exponential differentiation theorem
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Chain rule
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Mean value theorem
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Cauchy's mean value theorem
A
Correct answer
Explanation
The exponential differentiation theorem states that the derivative of an exponential function is equal to the function itself.
The method of approximating the derivative of a function using finite differences is called:
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Forward Difference Method
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Backward Difference Method
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Central Difference Method
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Richardson Extrapolation
A
Correct answer
Explanation
The Forward Difference Method is a simple numerical method for approximating the derivative of a function.
What is the derivative of the function (f(x) = x^3 - 2x^2 + 3x - 4)?
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\(3x^2 - 4x + 3\)
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\(3x^2 - 2x + 3\)
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\(x^3 - 4x^2 + 3x\)
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\(x^3 - 2x^2 + 3\)
A
Correct answer
Explanation
The derivative of the function (f(x) = x^3 - 2x^2 + 3x - 4) can be found using the power rule of differentiation. The power rule states that if (f(x) = x^n), then (f'(x) = nx^(n-1)). Applying this rule to each term of the function, we get: (f'(x) = 3x^2 - 4x + 3).
Find the derivative of the function (f(x) = x^3 - 2x^2 + 3x - 4).
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\(f'(x) = 3x^2 - 4x + 3\)
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\(f'(x) = 3x^2 - 2x + 3\)
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\(f'(x) = 3x^2 - 4x - 3\)
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\(f'(x) = 3x^2 - 2x - 3\)
A
Correct answer
Explanation
To find the derivative of the function, we can use the power rule: (\frac{d}{dx}x^n = nx^(n-1)). Applying this rule to each term of the function, we get: (f'(x) = \frac{d}{dx}(x^3 - 2x^2 + 3x - 4) = 3x^2 - 2(2x) + 3(1) - 0 = 3x^2 - 4x + 3).