Question

If set $A$ represents the range of the function $f\left(x\right)=\left[\sin x\right]$ (where [.] denotes the greatest integer function), then the number of subsets of $A$ is

Answer 1

We know $\sin x\in [-1,1]$
$\Rightarrow \left[\sin x\right]\in \{-1,0,1\}=A$
$\therefore$ Number of subsets of $A=2^{n\left(A\right)}=2^3=8$