Question
Differentiate the following from the first principle

$\text{x}^2\text{e}{^\text{x}}$

Answer

We have, 

$\text{f}(\text{x})=\text{x}^2\text{e}^\text{x}$

$\because\text{f}'(\text{x})=\lim_\limits{\text{h}\rightarrow0}\frac{\text{f}(\text{x}+\text{h})-\text{f}(\text{x})}{\text{h}}$

$=\lim_\limits{\text{h}\rightarrow0}\frac{\text{x}^2\text{e}^\text{x}\text{e}^\text{h}+\text{h}^2\text{e}^\text{x}\text{e}^\text{h}+2\text{xhe}^\text{x}\text{e}^\text{h}-\text{x}^2\text{e}^\text{x}}{\text{h}}$

$=\lim_\limits{\text{h}\rightarrow0}\text{x}^2\text{e}^\text{x}\frac{(\text{e}^\text{h}-1)}{\text{h}}+\text{e}^\text{x}\text{e}^\text{h}\frac{(\text{h}^2+\text{2xh})}{\text{h}}\ \Big[\because\frac{\text{e}^\text{h}-1}{\text{h}}-1\Big]$

$\therefore\text{x}^2\text{e}^\text{x}+\text{e}^\text{x}(0+\text{2x})$

$=\text{x}^2\text{e}^\text{x}+\text{2xe}^\text{x}$

$=\text{e}^\text{x}(\text{x}^2+\text{2x})$

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

If $\theta_1,\theta_2,\theta_3,....\theta_\text{n}$ are in A.P., whose common difference is d, show that $\sec\theta_1\cdot\sec\theta_2+\sec\theta_2+\sec\theta_3+\dots+\sec\theta_{\text{n}-1}\cdot\sec\theta_\text{n}=\frac{\tan\theta_\text{n}-\tan\theta_1}{\sin\text{d}}$
Find the equations of the circles passing through two points on y-axis at distances 3 from the origin and having radius 5.
In a survey of 200 students of a school, it was found that 120 study Mathematics, 90 study Physics and 70 study Chemistry, 40 study Mathematics and Physics, 30 study Physics and Chemistry, 50 study Chemistry and Mathematics and 20 none of these subjects. Find the number of students who study all the three subjects.
Show that $\sin100^\circ-\sin10^\circ$ is positive.
Show that the equation $x^2-2 y^2-2 x+8 y-1=0$ represents a hyperbola. Find the coordinates of the centre, lengths of the axes, eccentricity, latusrectum, coordinates of foci and vertices and equations of directrices of the hyperbola.
A box contains 10 red marbles, 20 blue marbles and 30 green marbles. 5 marbles are drawn at random. from the box, what is the probability that:
  1. All are blue?
  2. At least one is green?
Four point A(6, 3), B(-3, 5), C(4, -2) and D(x, 3x) are given in such a way that $\frac{\triangle\text{DBC}}{\triangle\text{ABC}}=\frac{1}{2}$, find x.
Evaluate:
$\lim\limits_{\text{x} \rightarrow0}\frac{\sqrt{2}-\sqrt{1+\cos\text{x}}}{\sin^{2}\text{x}}$
Determine the points xy-plane equidistant from the points A(1, -1, 0), B(2, 1, 2) and C(3, 2, -1).
Prove that $\text{x}^{2\text{n}-1}+\text{y}^{2\text{n}-1}$ is divisible by x + y for all $\text{n}\in\text{N}.$