Applicartions Of Derivatives Test

Applicartions Of Derivatives

This is Applicartions of Derivatives Test-05 for CBSE class 12 Maths.. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

1
Let f (x) = \({({x^2} - 4)^{1/3}}\), then f has a
  • A
    local maxima at x = 0
  • B
    none of these
  • C
    local minima at x = 0
    Correct
  • D
    point of inflextion at x = 0
2
The function f (x) = \({x^3}\) has a
  • A
    none of these
  • B
    local maxima at x = 0
  • C
    local minima at x = 0
  • D
    point of inflexion at = 0
    Correct
3
The minimum value of (x) =sin x cos x is
  • A
    0
  • B
    \(\frac{1}{2}\)
  • C
    none of these.
  • D
    \( - \frac{1}{2}\)
    Correct
4
The stone projected vertically upwards moves under the action of gravity alone and its motion is described by x = 49 t – 4.9 \({t^2}\) . It is at a maximum height when
  • A
    t = 0
  • B
    none of these
  • C
    t = 5
    Correct
  • D
    t = 10
5
The function \(f{\text{ }}\left( x \right){\text{ }} = {\text{ }}\left| {{\text{ }}x{\text{ }}} \right|\) has
  • A
    only one minima
    Correct
  • B
    no maxima or minima
  • C
    only one maxima
  • D
    none of these
6
If a differentiable function f (x) has a relative minimum at x = 0, then the function y = f (x) + a x + b has a relative minimum at x = 0 for
  • A
    all a > 0.
  • B
    all b > 0
  • C
    all b if a = 0
    Correct
  • D
    all a and all b
7
Let f (x) be differentiable in (0, 4) and f (2) = f (3) and S = {c : 2 < c < 3, f’ (c) = 0 } then
  • A
    S has exactly one point
  • B
    S has atleast one point
    Correct
  • C
    S = { }
  • D
    none of these
8
Every continuous function is
  • A
    differentiable.
  • B
    not differentiable
    Correct
  • C
    not differentiable
  • D
    decreasing
9
Rolle’s Theorem is not applicable to the function \(f\left( x \right){\text{ }} = {\text{ }}\left| {{\text{ }}x{\text{ }}} \right|\) for \( - 2 \leqslant x \leqslant 2\) because
  • A
    f (x) is not derivable for x = 0
    Correct
  • B
    f ( – 2) = f (2)
  • C
    none of these
  • D
    f (x) is continuous for \( - 2 \leqslant x \leqslant 2\) because
10
If \(x \in \left( {0,\frac{\pi }{2}} \right),\) then
  • A
    sin x < x < tan x
    Correct
  • B
    tan x < x < sin x
  • C
    x< sin x < tan x
  • D
    none of these
11
Rolle’s theorem is not applicable to function f(x) = | x | in the interval [ – 3, 3] because
  • A
    f is continuous in( – 3, 3)
  • B
    \(f{\text{ }}\left( x \right)0\forall x{\text{ }}in{\text{ }}\left[ {\;--\;3,{\text{ }}3} \right]\)
  • C
    f is not derivable in ( – 3, 3)
    Correct
  • D
    f (3) = f ( – 3)
12
For f (x) = \({(x - 1)^{2/3}}\), the mean value theorem is applicable to f (x) in the interval
  • A
    any finite interval.
  • B
    [2, 4]
    Correct
  • C
    [0, 2]
  • D
    [ – 2, 2]
13
Let f (x) satisfy the requirements of Lagrange’s mean value theorem in [0, 2] . If f (0) = 0 and f ‘ \((x) \leqslant \frac{1}{2}\) for all in [0, 2], then
  • A
    f (x) = 2 x
  • B
    \(\left| {{\text{ }}f{\text{ }}\left( x \right){\text{ }}} \right| \leqslant 2\)
  • C
    f (x0 = 3 for atleast one x in [0, 2]
  • D
    \(f{\text{ }}\left( x \right) \leqslant 1\)
    Correct
14
\(\mathop {\lim }\limits_{x \to \infty } f(x)\), where f (x) = \(\sqrt {\frac{{x - \sin x}}{{x + {{\cos }^2}x}}} \), is equal to
  • A
    none of these
  • B
    1
    Correct
  • C
    \(\begin{array}{*{20}{l}} \infty \end{array}\)
  • D
    0
15
For a real number x, let [x] denote the greatest integer less than or equal to x thenf (x) = \(\frac{{\tan (\pi [x - \pi ])}}{{1 + {{[x]}^2}}}\)is
  • A
    continuous for some x
  • B
    continuous at all x but f ‘ (x) does not exist
  • C
    f ‘ (x) exists for all x
    Correct
  • D
    f ‘ (x) exists for all x but f ‘’ (x) does not exist