Q.
If$f(x) = ae^{|x|} + b|x|^{2}$; $a,\ b\ \in R$ and $f(x)$ is differentiable at $x = 0$. Then $a$ and $b$ are
A) $a = 0,\ b \in R$
B) $a = 1,\ b = 2$
C) $b = 0,\ a \in R$
D) $a = 4,\ b = 5$
Explanation
(a)
Given, $f(x) = ae^{|x|} + b\ |x|^{2}$
We know $e^{|x|}$ is not differentiable at $x = 0$ and $|x|^{2}$ is differentiable at $x = 0$
$\therefore\ \ f(x)$ is differentiable at $x = 0$, if $a = 0$ and $b \in R$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.