Question

Let $f\left(x\right)=\{\begin{array}{c}1+|x|,x<-1\\ \left[x\right],x\ge -1\end{array}$ where $[\cdot ]$ denotes the greatest integer function. Then $f\left\{f\right(-2.3\left)\right\}$ is equal to

• A. $4$
• B. $2$
• C. $-3$
• D. $3$

Answer 1

The correct option is D $3$

$f\left(x\right)=\{\begin{array}{c}1+|x|,x<-1\\ \left[x\right],x\ge -1\end{array}$
.

$f(-2.3)=1+|-2.3|=3.3\dots (\because x<-1$)
.

hence, $f\left(f(-2.3)\right)=f\left(3.3\right)=\left[3.3\right]=3$

$f\left(f(-2.3)\right)=3$