Q. The function defined by $f(x) = \left\{ \begin{array}{r} \left( x^{2} + e^{\frac{1}{2 - x}} \right)^{- 1}\ x \neq 2 \\ k,\ \ \ \ \ \ \ \ \ \ x = 2 \end{array} \right.\$ is continuous from right at the point $x = 2$, then $k$ is equal to

A) 0
B) $\frac{1}{4}$
C) $- \frac{1}{2}$
D) None of these
Explanation

(b)
Since, $\lim_{x{\rightarrow 2}^{+}}{f(x) = f(2) = k}$
$\Rightarrow \ \ \ k = \lim_{h \rightarrow 0}{f(2 + h)}$
$\Rightarrow \ \ \ k = \underset{h \rightarrow 0}{lim}\left\lbrack (2 + h)^{2} + e^{\frac{1}{2 - (2 + h)}} \right\rbrack^{- 1}\$
$\Rightarrow \ \ \ \underset{h \rightarrow 0}{lim}\ \ \ \left\lbrack 4 + h^{2} + 4h + e^{\frac{- 1}{h}} \right\rbrack^{- 1} = \frac{1}{4}$

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.