Q. If the function $f:R \rightarrow R$ given by $f(x) = \left\{ \begin{array}{r} x + a,\ if\ x \leq 1 \\ 3 - x^{2},\ \ if\ x > 1 \end{array} \right.\$ is continuous at $x = 1$, thyen $a$ is equal to

A) 4
B) 3
C) 2
D) 1
Explanation

(d)
LHL$= \lim_{x \rightarrow 1^{-}}f(x) = \lim_{h \rightarrow 0}1 - h + a = 1 + a$
RHL$= \lim_{x \rightarrow 1^{+}}f(x) = \lim_{h \rightarrow 0}3 - (1 + h)^{2} = 2$
For $f(x)$ to be continuous, LHL=RHL
$\Rightarrow 1 + a = 2\ \ \ \ \Rightarrow \ \ \ a = 1$

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

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