MCQ
Let $S = \{\lambda ,\mu \} \in R \times R:f\left( t \right) = \left( {\left| \lambda  \right|{e^{\left| t \right|}} - \mu } \right)$. $\sin \left( {2\left| t \right|} \right),t \in R$ , is a differentiable function$\}$ . Then $S$ is a subest of?
  • $R \times \left[ {0,\infty } \right)$
  • B
    $\left( { - \infty ,0} \right) \times R$
  • C
    $\left[ {0,\infty } \right) \times R$
  • D
    $R \times \left( { - \infty ,0} \right)$

Answer

Correct option: A.
$R \times \left[ {0,\infty } \right)$
a
$S = \left\{ {\lambda ,\mu } \right\} \in R \times R:f\left( t \right) = \left( {\left| \lambda  \right|{e^{\left| t \right|}} - \mu } \right)\sin \left( {2\left| t \right|} \right),$

$t \in R$

$f\left( t \right) = \left( {\left| \lambda  \right|{e^{\left| t \right|}} - \mu } \right)\sin \left( {2\left| t \right|} \right)$

$\left\{ \begin{array}{l} \left( {\left| \lambda  \right|{e^t} - \mu } \right)\sin 2t\,\,\,\,\,\,\,\,t > 0\\ \left( {\left| \lambda  \right|{e^{ - t}} - \mu } \right)\left( { - \sin 2t\,} \right)\,\,\,\,\,\,\,t < 0 \end{array} \right.$

$f'(t)$

$ = \left\{ \begin{array}{l} \left( {\left| \lambda  \right|{e^t}} \right)\sin 2t + \left( {\left| \lambda  \right|{e^t} - \mu } \right)\left( {2\cos 2t} \right)\,\,\,t > 0\\ \left| \lambda  \right|{e^{ - t}}\sin 2t + \left( {\left| \lambda  \right|{e^{ - t}} - \mu } \right)\left( { - 2\cos 2t} \right)\,\,\,\,t < 0 \end{array} \right.$

As, $f(t)$ is differentiable

$\therefore LHD = RHD$ at $t=0$

$\left| \lambda  \right|.\sin 2\left( 0 \right) + \left( {\left| \lambda  \right|{e^0} - \mu } \right)2\cos \left( 0 \right)$

$ = \left| \lambda  \right|{e^0}.\sin 2\left( 0 \right) - 2\cos \left( 0 \right)\left( {\left| \lambda  \right|{e^0} - \mu } \right)$

$ \Rightarrow 0 + \left( {\left| \lambda  \right| - \mu } \right)2 = 0 - 2\left( {\left| \lambda  \right| - \mu } \right)$

                  $4\left( {\left| \lambda  \right| - \mu } \right) = 0$

                  $\left| \lambda  \right| = \mu $

So, $S \equiv \left( {\lambda ,\mu } \right) = \left\{ {\lambda  \in R\;and\;\mu  \in \left[ {0,\infty } \right)} \right\}$

Therefore set $S$ is subset of $R \times \left[ {0,\infty } \right)$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

A and B are two events such that P(A) = 0.25 and P(B) = 0.50. The probability pf both happening together is 0.14. The probability of both A and B hot happening is.
  1. 0.39
  2. 0.25
  3. 0.11
  4. None of these.
Let $k_1$, $k_2$ be the maximum and minimum values of $k$ for which the system of equations given by

$x + ky = 1$ ; $kx + y = 2$;  $x + y = k$  are consistent then $k_1^2 + k_2^2$ is equal to

If $\int_{\sin x}^1 {{t^2}f(t)\;dt = 1 - \sin x} $,  $x \in \left( {0,\frac{\pi }{2}} \right)$ then $f\;\left( {\frac{1}{{\sqrt 3 }}} \right)$ equal to
Let $\lambda \in Z, \vec{a}=\lambda \hat{i}+\hat{j}-\hat{k}$ and $\vec{b}=3 \hat{i}-\hat{j}+2 \hat{k}$. Let $\overrightarrow{ c }$ be a vector such that $(\vec{a}+\vec{b}+\vec{c}) \times \vec{c}=\overrightarrow{0}, \vec{a} \cdot \vec{c}=-17$ and $\vec{b} \cdot \vec{c}=-20$ Then $|\overrightarrow{ c } \times(\lambda \hat{i}+\hat{j}+\hat{ k })|^2$ is equal to
The value of $\int\limits^1_0\tan^{-1}\Big(\frac{2\text{x}-1}{1+\text{x}-\text{x}^2}\Big)\text{ dx},$ is:
  1. 1
  2. 0
  3. -1
  4. $\frac{\pi}{4}$
If $R$ and $R^{\prime}$ are symmetric relations (not disjoint) on a set $A$, then the relation $R \cap R^{\prime}$ is
If $\text{y}=\text{e}^{-\text{x}}(\text{A}\cos\text{x}+\text{B}\sin\text{x}),$ then y is a solution of:
  1. $\frac{\text{d}^2\text{y}}{\text{dx}^2}+2\frac{\text{dy}}{\text{dx}}=0$
  2. $\frac{\text{d}^2\text{y}}{\text{dx}^2}-2\frac{\text{dy}}{\text{dx}}+2\text{y}=0$
  3. $\frac{\text{d}^2\text{y}}{\text{dx}^2}+2\frac{\text{dy}}{\text{dx}}+2\text{y}=0$
  4. $\frac{\text{d}^2\text{y}}{\text{dx}^2}+2\text{y}=0$
If $f(x)$ = $\int\limits_0^x {2\,({{\cos }^{2\,}}\,3t\, + \,3\,{{\sin }^{2\,}}\,3t)dt} $ , then $f ( x + \pi )$ is eual to
Choose the correct answer in Exercise:
The value of the integral   $\int^{1}_{\frac{1}{3}}\frac{(\text{x}-\text{x}^{3})^{\frac{1}{3}}}{\text{x}^{4}}\text{dx}\ \text{is}$
  1. 6
  2. 0
  3. 3
  4. 4
Perpendicular distance of the point $P (x, y, z)$ from $z$ axis is :