Practicing Success
$f(x)=\left\{\begin{matrix}xe^{-(\frac{1}{x}+\frac{1}{|x|})},&x≠0\\a,&x=0\end{matrix}\right.$. Value of ‘a’ such that f(x) is differentiable at x = 0, is equal to |
1 -1 0 none of these |
none of these |
$\underset{x→0^-}{\lim}xe^{-\frac{1}{x}+\frac{1}{x}}=x×1=0=LHL$ $\underset{x→0^+}{\lim}xe^{-\frac{1}{x}-\frac{1}{x}}=x×e^{-∞}=0=RHL$ $⇒a=0$ for continuity $LHD=f'(0^-)=\underset{h→0^-}{\lim}\frac{-he^{-(-\frac{1}{h}+\frac{1}{h})-a}}{-h}=\underset{x→0}{\lim}\frac{-h-a}{-h}=1$ $RHD=f'(0^+)=\underset{h→0}{\lim}\frac{he^{-(\frac{1}{h}+\frac{1}{h})-a}}{h}=0$ $RHD≠LHD$ ⇒ function is not differentiable at x = 0 |