Calculus: Differentiability and Curve Properties - Class XI

Comprehensive quiz covering tangents, normals to curves, and function differentiability concepts including piecewise functions, derivatives at boundary points, and implicit differentiation.

50 Questions Published

Questions

Question 1 Multiple Choice (Single Answer)

If slope of tangent of curve $y=\dfrac{x}{b-x}$ at $(1,1)$ be $2$ then $b=$

  1. $1$
  2. $2$
  3. $0$
  4. $-1$
  5. $-2$
Question 2 Multiple Choice (Single Answer)

The general solution of the differential equation $\sin{2x}\left( \cfrac { dy }{ dx } -\sqrt { \tan { x }  }  \right) -y=0$ is $y\phi(x)=x+c$ then ${ \Phi  }^{ 1 }\left( \cfrac { \pi  }{ 4 }  \right) $ is _____

  1. $1$
  2. $-1$
  3. $\cfrac{1}{\sqrt{3}}$
  4. $\sqrt{-3}$
Question 3 Multiple Choice (Single Answer)

The derivative of a differentiable even function is always an even function.

  1. True
  2. False
Question 4 Multiple Choice (Single Answer)

If $g$ is the inverse of $f$ and $\displaystyle f'\left( x \right) =\frac { 1 }{ 1+{ x }^{ 3 } } $, then $g'\left( x \right) $ is equal to

  1. $1+{ \left[ g\left( x \right) \right] }^{ 3 }$
  2. $\displaystyle \frac { 1 }{ 1+{ \left[ g\left( x \right) \right] }^{ 3 } } $
  3. ${ \left[ g\left( x \right) \right] }^{ 3 }$
  4. None of these
Question 5 Multiple Choice (Single Answer)

If $y=mx+c$ is the normal at a point $(8,8)$  on the parabola ${ y }^{ 2 }=8x$ Find $m$

  1. $-2 $
  2. $8 $
  3. $10 $
  4. $16 $
Question 6 Multiple Choice (Single Answer)

Function $ f(x)= \sin^{-1} (3x-4x^3) $ is-

  1. Always differentiable
  2. Not differentiable at 2 points
  3. Not continuous at 2 points
  4. Not differentiable at 3 points
Question 7 Multiple Choice (Single Answer)

If $\log \sqrt{x^2+y^2}=\tan^{-1}\left(\dfrac{y}{x}\right)$ , then $\dfrac{dy}{dx}$ is:

  1. $1$
  2. $2$
  3. $\dfrac{2x}{\sqrt{x^2+y^2}}$
  4. $\dfrac{x+y}{x-y}$
Question 8 Multiple Choice (Single Answer)

If $y = \left| {\cos x} \right| + \left| {\sin x} \right|$ , then ${\dfrac{dy} {dx}}$ at $x = {\dfrac {2\pi } 3}$ is

  1. ${1 \over 2}\left( {\sqrt 3 + 1} \right)$
  2. $2\left( {\sqrt 3 - 1} \right)$
  3. ${1 \over 2}\left( {\sqrt 3 - 1} \right)$
  4. none of these
Question 9 Multiple Choice (Single Answer)

The line $y =\sqrt{2}x + 4\sqrt{2}$ is a normal to $y^{2} =4ax$ then a = 

  1. $2$
  2. $\sqrt{2}$
  3. $1$
  4. $-1$
Question 10 Multiple Choice (Single Answer)

The  number of points where $f(x) = \mid | x |^2 - 5| x | + 6 \mid $ is non-derivable is/are

  1. 1
  2. 3
  3. 4
  4. 5
Question 11 Multiple Choice (Single Answer)
State whether the given statement is True or False.
A function is said to be differentiable in an interval $(a, b)$, if it is differentiable at every point of $(a, b)$.
  1. True
  2. False
Question 12 Multiple Choice (Single Answer)

Let $f(x) = \left{\begin{matrix} 2 + 1,& x \leq 1\ x^{2} + 2, & 1 < x \leq 2\ 4x - 2, & x > 2\end{matrix}\right.$ then the number of points where $f(x)$ is non-differentiable, is equal to

  1. $0$
  2. $1$
  3. $2$
  4. $3$
Question 13 Multiple Choice (Single Answer)

$f(x)=|\cos x|$ is not differentiable for the points given by $x=?$

  1. $\dfrac{\pi}{2}$
  2. $(2n+1)\pi, \forall n\in I$
  3. $(2n+1)\dfrac{\pi}{2}\forall n\in I$
  4. $0$
Question 14 Multiple Choice (Single Answer)

If $g$ is the inverse of $f$ and $f'(x)=\dfrac{1}{1+x^{3}}$, then $g'(x)$ is equal to.

  1. $1+[g(x)]^{3}$
  2. $\dfrac{1}{1+[g(x)]^{3}}$
  3. $[g(x)]^{3}$
  4. $None\ of\ these$
Question 15 Multiple Choice (Single Answer)

If $f(x)=(x^2-4)\left|x^3-6x^2+11x-6\right|+\dfrac{x}{1+|x|}$, then the set of points at which the function $f(x)$ is not differentiable is?

  1. $\{-2, 2, 1, 3\}$
  2. $\{-2, 0, 3\}$
  3. $\{-2, 2, 0\}$
  4. $\{1, 3\}$
Question 16 Multiple Choice (Single Answer)

If $\sqrt { { x }^{ 2 }+{ y }^{ 2 } } ={ e }^{ t }$ where $t=\sin ^{ -1 }{ \left( \cfrac { y }{ \sqrt { { x }^{ 2 }+{ y }^{ 2 } }  }  \right)  } $ then $\cfrac { dy }{ dx } $ is equal to

  1. $\cfrac { x-y }{ x+y } $
  2. $\cfrac { x+y }{ x-y } $
  3. $\cfrac { y-x }{ y+x } $
  4. $\cfrac { x-y }{ 2x+y } $
Question 17 Multiple Choice (Single Answer)

Value of c is :-
$\dfrac{d}{dx}(c\ ^{f(x)}) = f' (x)e^{f(x)}$

  1. $e$
  2. $e^2$
  3. $1$
  4. $ln{x}$
Question 18 Multiple Choice (Single Answer)

The condition that the line $\dfrac{x}{a}+\dfrac{y}{b}=1$ is tangent to the curve $x^{2/3}+y^{2/3}=1$ is

  1. $a^{2}+b^{2}=2$
  2. $a^{2}+b^{2}=1$
  3. $\dfrac{1}{a^{2}}+\dfrac{1}{b^{2}}=1$
  4. $a^{2}$
Question 19 Multiple Choice (Single Answer)

If line $PQ$, whose equation is $y = 2x + k,$  is a normal to the parabola whose vertex is   $(-2,3)$ and the axis parallel to the $x$-axis with latus rectum equal to $2$, then the possible value of k is

  1. $\dfrac{{58}}{8}$
  2. $\dfrac{{50}}{8}$
  3. $1$
  4. $-1$
Question 20 Multiple Choice (Single Answer)

If $y = \dfrac { 1 } { 1 + x ^ { n - m } + x ^ { p - m } } + \dfrac { 1 } { 1 + x ^ { m - n } + x ^ { p - n } } + \dfrac { 1 } { 1 + x ^ { m - p } + x ^ { n - p } }$ then $\dfrac { d y } { d x }$ at $x = e ^ { m ^ { n p } }$ is equal to

  1. $e ^ { m n p }$
  2. $e ^ { m n / p }$
  3. $e ^ { n p / m }$
  4. $0$
Question 21 Multiple Choice (Single Answer)

Let f(x) be a differentiable function and $f\left( \alpha  \right) = f\left( \beta  \right) = 0,\left( {\alpha  < \beta } \right)$, then in the interval $\left( {\alpha ,\beta } \right)$

  1. $f\left( x \right) + f'\left( x \right) = 0$ has at least one root.
  2. $f\left( x \right) - f'\left( x \right) = 0$ has at least one root.
  3. $f\left( x \right) . f'\left( x \right) = 0$ has at least one root.
  4. None of these
Question 22 Multiple Choice (Single Answer)

If $y = \log \left( \frac { 1 + x } { 1 - x } \right) ^ { 1 / 4 } - \frac { 1 } { 2 } \tan ^ { - 1 } x ,$ then $\frac { d y } { d x } =$

  1. $\frac { x ^ { 2 } } { 1 - x ^ { 4 } }$
  2. $\frac {2 x ^ { 2 } } { 1 - x ^ { 4 } }$
  3. $\frac { x ^ { 2 } } { 2 \left( 1 - x ^ { 4 } \right) }$
  4. None of these
Question 23 Multiple Choice (Single Answer)

If f'$\left( x \right) =\sqrt { { 2x }^{ 2 }-1 } $ and y=f$\left( { x }^{ 2 } \right) $ then $\dfrac { dy }{ dx } $ at x=1 is

  1. 2
  2. 1
  3. -2
  4. none of these
Question 24 Multiple Choice (Single Answer)

A differentiable function function $y = h(x)$ satisfies $\displaystyle \overset{x}{\underset{0}{\int}} (x - t + 1)h(t)dt = x^4 + x^2; \forall x \ge 0$, then value of $h(0) + h'(0)$ is equal to

  1. $0$
  2. $1$
  3. $e^2$
  4. $2$
Question 25 Multiple Choice (Single Answer)

Area of the triangle formed by the lines $x-y=0, x+y=0$ and ant tangent to the hyparabola $x^{2}-y^{2}=a^{2}$ is 

  1. $|a|$
  2. $\dfrac{1}{2}|a|$
  3. $a^{2}$
  4. $\dfrac{1}{2}a^{2}$
Question 26 Multiple Choice (Single Answer)

If $x = \exp \left{ \tan ^ { - 1 } \left( \frac { y - x ^ { 2 } } { x ^ { 2 } } \right) \right}$ then $\frac { d y } { d x } =$

  1. $2 x [ 1 + \tan ( \log x ) ] + x \cdot \sec ^ { 2 } ( \log x )$
  2. $x [ 1 + \tan ( \log x ) ] + \sec ^ { 2 } ( \log x )$
  3. $2 x [ 1 + \tan ( \log x ) ] + x ^ { 2 } \sec ^ { 2 } ( \log x )$
  4. None of these
Question 27 Multiple Choice (Multiple Answers)

Consider the function $f(x)=\mathrm{s}\mathrm{g}\mathrm{n} x$ and $g(x)=x\left ( 1-x^{2} \right )$. Which of the following does NOT hold good?

  1. $(fog)(x)$ is neither odd nor even
  2. $(gof)(x)$ is odd
  3. $(fog)(x)$ is neither continuous nor differentiable for some $x$ on $\left ( -\infty, \infty \right )$
  4. $(fog)(x)$ is continuous and differentiable for every $x$ on $\left ( -\infty, \infty \right )$
Question 28 Multiple Choice (Single Answer)

The set of all points of differentiability of the function $\displaystyle f(x) = \dfrac{\sqrt{x + 1} 1}{\sqrt{x}}$ for $x$  and $f(0)$ = 0 is

  1. $(\infty , \infty)$
  2. $[0 , \infty)$
  3. $(0 , \infty)$
  4. $(\infty$ , $\infty)$ $-\left \{ 0 \right \}$
Question 29 Multiple Choice (Single Answer)

If the graph of the equation $y = 2x^2 - 6x + C$ is tangent to the $x$-axis, the value of $C$ is

  1. $3$
  2. $3\dfrac{1}{2}$
  3. $4$
  4. $4\dfrac{1}{2}$
  5. $5$
Question 30 Multiple Choice (Single Answer)

$f\left( x \right) =\begin{cases} x;\quad x<1 \ 3-x;\quad 1\le x\le 3 \end{cases}$ then $f^{'}(x)=$

  1. $2$
  2. $0$
  3. $-1$
  4. Does not exist
Question 31 Multiple Choice (Single Answer)

The domain of the derivative of the function
$\displaystyle f\left ( x \right )=\begin{cases}
\tan^{-1}x & \text{ if } \left | x \right |\leq 1 \
\frac{1}{2}\left ( \left | x \right |-1 \right ) & \text{ if } \left | x \right |> 1
\end{cases}$

  1. $R\sim \left \{ 0 \right \}$
  2. $R\sim \left \{ 1 \right \}$
  3. $R\sim \left \{ -1 \right \}$
  4. $R\sim \left \{ -1, 1 \right \}$
Question 32 Multiple Choice (Single Answer)

Let $f(x)=ax^2+bx+c$ such that $f(1)=f(-1)$ and a, b, c are in Arithmetic Progression.

Then find what kind of progression $f'(a), f'(b), f'(c)$ form.

  1. A.P.
  2. G.P.
  3. H.P.
  4. Arithmetico-geometric progression
Question 33 Multiple Choice (Single Answer)

If $y=\displaystyle\dfrac{1}{a-z}$, then $\displaystyle\dfrac{dz}{dy}$ is:

  1. $(a-z)^2$
  2. $-(z-a)^2$
  3. $(z+a)^2$
  4. $-(z+a)^2$
Question 34 Multiple Choice (Multiple Answers)

Which of the following given statements is/are correct?

  1. If L.H.D $\neq $ R.H.D, then $f(x)$ is not differentiable at $x= c$
  2. If a function is differentiable at a point, it is necessarily continuous at the point.
  3. If a function is differentiable at each $x \in R$ then it is said to be every where differentiable.
  4. $\dfrac{d}{dx}(c f (x)) =c \dfrac{d}{dx} (f (x))$, where $c$ is a constant.
Question 35 Multiple Choice (Single Answer)

The value of $\displaystyle \frac{d}{dx} (|x-1|+ |x-5|) $ at x = 3 is

  1. -2
  2. 0
  3. 2
  4. 4
Question 36 Multiple Choice (Single Answer)

Let $f : R \rightarrow R$ be a function defined by $f(x)= \max\left { x,  x^3 \right }$. The set of all points where $f(x)$ is NOT differentiable is:

  1. $\{-1, 1\}$
  2. $\{-1, 0\}$
  3. $\{0, 1\}$
  4. $\{-1, 0, 1\}$
Question 37 Multiple Choice (Single Answer)

If $f(x) = \left{\begin{matrix}e^x+ax & x< 0 \ b(x-1)^2 & x \geq 0 \end{matrix}\right.$ is differentiable at $x= 0$, then $(a, b)$ is

  1. $(-3, -1)$
  2. $(-3, 1)$
  3. $(3, 1)$
  4. $(3, -1)$
Question 38 Multiple Choice (Single Answer)

If $f(x) =x[x \sqrt{x}-\sqrt{x+1}]$, then:

  1. $f(x)$ is continuous but not differentiable at $x= 0$
  2. $f(x)$ is not differentiable at $x= 0$
  3. $f(x)$ is differentiable at $x= 0$
  4. none of these
Question 39 Multiple Choice (Single Answer)

If $y = \dfrac {1}{1 + x^{n - m} + x^{p - m}} + \dfrac {1}{1 + x^{m - n} + x^{p - n}} + \dfrac {1}{1 + x^{m - p} +x^{n - p}}$ then $\dfrac {dy}{dx}$ at $e^{m^{n^{p}}}$ is equal to

  1. $e^{mnp}$
  2. $e^{mn/p}$
  3. $e^{np/m}$
  4. $0$
Question 40 Multiple Choice (Multiple Answers)

If the distance between a tangent to the parabola $y^{2} = 4x$ and a parallel normal to the same parabola is $2\sqrt{2}$, then possible values of gradient of either of them are:

  1. $-1$
  2. $+1$
  3. $-\sqrt{\sqrt{5} - 2}$
  4. $+\sqrt{\sqrt{5} - 2}$
Question 41 Multiple Choice (Single Answer)

Consider the function $f(x)=\begin{cases} x^2 \sin \dfrac{1}{x};x\neq 0 \ 0 ; otherwise  \end{cases}$
then,

  1. $f$ is derivable at $x=0$
  2. $f $ is not derivable at $x=0$
  3. $f$ is derivable at $x=0$ and $f'(0)=0$
  4. $f$ is derivable at $x=0$ and $f'(0)\neq0$
Question 42 Multiple Choice (Single Answer)

Consider the following statements:
$1.$ Derivative of $f(x)$ may not exist at some point.
$2.$ Derivative of $f(x)$ may exist finitely at some point.
$3.$ Derivative of $f(x)$ may be infinite (geometrically) at some point.
Which of the above statements are correct?

  1. $1$ and $2$ only
  2. $2$ and $3$ only
  3. $1$ and $3$ only
  4. $1, 2$ and $3$
Question 43 Multiple Choice (Single Answer)
$f(x)= \left\{\begin{matrix}x^2+3x+a & \text{for}\, x \leq 1 \\ bx+2 & \text{for}\, x > 1 \end{matrix}\right.$ 
is everywhere differentiable. Then value of constant $b$ is
  1. $5$
  2. $3$
  3. $\dfrac{1}{5}$
  4. None of these
Question 44 Multiple Choice (Single Answer)

A function is defined in $(0, \infty)$ by
$f(x) = \left{\begin{matrix}1 - x^{2} & for & 0 < x  \leq 1\ \ln\ x & for & 1 < x \leq 2\ \ln\ 2 - 1 + 0.5x & for & 2 < x < \infty\end{matrix}\right.$
Which one of the following is correct in respect of the derivative of the function, i.e., $f'(x)$?

  1. $f'(x) = 2x$ for $0 < x \leq 1$
  2. $f'(x) = -2x$ for $0 < x \leq 1$
  3. $f'(x) = -2x$ for $0 < x < 1$
  4. $f'(x) = 0$ for $0 < x < \infty$
Question 45 Multiple Choice (Single Answer)
$f(x)= \left\{\begin{matrix}x^2+3x+a & \text{for}\, x \leq 1 \\ bx+2 & \text{for}\, x > 1 \end{matrix}\right.$
is everywhere differentiable. Then value of constant $a$ is
  1. $3$
  2. $\dfrac{1}{3}$
  3. $5$
  4. None of these
Question 46 Multiple Choice (Single Answer)


 lf $\mathrm{f}(\mathrm{x})=\left{\begin{array}{l}1, \mathrm{x}<0\1+ \mathrm{s}\mathrm{i}\mathrm{n}\mathrm{x}, 0\leq \mathrm{x}</\pi _{2} \end{array}\right.$, then derivative of f(x) at$\mathrm{x}=0$

  1. is equal to 1
  2. is equal to 0
  3. is equal to -1
  4. does not exist
Question 47 Multiple Choice (Single Answer)

If $f(x)=(4+x)^{n}$,$n \epsilon N$ and $f^{r}(0)$ represents the $r^{th}$ derivative of f(x) at x = 0, then the value of $\sum _{r=0}^{\infty}\frac{(f^{r}(0))}{r!}$ is equal to

  1. $2^{n}$
  2. $e^{n}$
  3. $5^{n}$
  4. $4^{n}$
Question 48 Multiple Choice (Single Answer)

Let $f(x)=\begin{cases}\begin{matrix} 1 & \forall &  x<0 \ 1+\sin x & \forall & 0\leq x\leq \dfrac{\pi}2\end{matrix}\end{cases}$ then what is the value of $f'(x)$ at $x=0?$

  1. $1$
  2. $-1$
  3. $\infty$
  4. Does not exist
Question 49 Multiple Choice (Single Answer)

The second order differential equation is :

  1. ${ y' }^{ 2 }+x={ y }^{ 2 }$
  2. $y'+y''+y=\sin { x } $
  3. $y'''+y''+y=0$
  4. $y'=y$
Question 50 Multiple Choice (Single Answer)

$f\left( x \right) = \left| {x - 1} \right| + \left| {x + 2} \right| + \left| {x - 3} \right|$ is not differentiable at

  1. 2 points
  2. 3 points
  3. 4 points
  4. 1 point