MCQ
If $y = 1 + x + {{{x^2}} \over {2!}} + {{{x^3}} \over {3!}} + .....\infty ,$ then ${{dy} \over {dx}} = $
  • $y$
  • B
    $y - 1$
  • C
    $y + 1$
  • D
    None of these

Answer

Correct option: A.
$y$
a
(a) $y = 1 + x + \frac{{{x^2}}}{{2!}} + \frac{{{x^3}}}{{3!}} + ......\infty $==>$y = {e^x}$

Differentiating with respect to  $x$ , we get $\frac{{dy}}{{dx}} = {e^x} = y$.

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

The angle between the lines whose direction cosines are connected by the relations $l + m + n = 0$ and $2lm + 2nl - mn = 0$, is
Let $\theta$ be the angle between the vectors $\vec{a}$ and $\vec{b}$, where $|\vec{a}|=4,|\vec{b}|=3 \quad \theta \in\left(\frac{\pi}{4}, \frac{\pi}{3}\right)$. Then $|(\vec{a}-\vec{b}) \times(\vec{a}+\vec{b})|^{2}+4(\vec{a} \cdot \vec{b})^{2}$ is equal to
If the function $f\,:\,R - \,\{ 1, - 1\}  \to A$ defined by $f\,(x)\, = \frac{{{x^2}}}{{1 - {x^2}}},$ is surjective, then $A$ is equal to
Let $f : Z \rightarrow Z$ be given by $\text{f(x)}=\begin{cases}\frac{\text{x}}{2}, \text{if x is even 0}, \text{if x is odd}\end{cases}\}.$ Then$, f$ is:
The area enclosed by the curves $y^2=x$ and $y=|x|$ is :
The sum of possible values of $x$ for $\tan ^{-1}( x +1)+\cot ^{-1}\left(\frac{1}{ x -1}\right)=\tan ^{-1}\left(\frac{8}{31}\right)$ is
If $f(x) = \left\{ \begin{array}{l}\frac{{1 - \cos x}}{x},\,x \ne 0\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,k,\,x = 0\end{array} \right.$ is continuous at $x = 0$ then $k = $
The matrix $A = \left[ {\begin{array}{*{20}{c}}1&{ - 3}&{ - 4}\\{ - 1}&{\,\,\,3}&{\,\,4}\\1&{ - 3}&{ - 4}\end{array}} \right]$ is nilpotent of index
The number of arbitrary constants in the general solution of a differential equation of fourth order are:
$f\left( x \right) = \left| {\begin{array}{*{20}{c}}
  {2{{\cos }^2}2x}&{\sin 2x}&{ - \sin x} \\ 
  {\sin 2x}&{2{{\sin }^2}x}&{\cos x} \\ 
  {\sin x}&{ - \cos x}&0 
\end{array}} \right|$,the value of $\int\limits_0^{\frac{\pi }{2}} {f'\left( x \right)} \,dx$ is equal to