Question:
Mark the correct alternative in the following question:
Let $f: \mathrm{R} \rightarrow \mathrm{R}$ be defined as $f(x)=\left\{\begin{array}{c}2 x, \text { if } x>3 \\ x^{2}, \text { if } 1
Then, find f(−1) + f(2) + f(4)
(a) 9
(b) 14
(c) 5
(d) none of these
Solution:
We have,
$f(x)=\left\{\begin{array}{c}2 x, \text { if } x>3 \\ x^{2}, \text { if } 1
Now,
$f(-1)+f(2)+f(4)$
$=3(-1)+2^{2}+2(4)$
$=-3+4+8$
$=9$
Hence, the correct alternative is option (a).