Question

If f(x)=3[x] +5, find f(x) if x= 4.3f(x)= -17f(x)= 17f(x)= 20f(x)= -20

Answer 1

It is given that

$f(x)=3\lbrack x\rbrack+5$

Now

$\begin{gathered} f(4.3)=3\lbrack4.3\rbrack+5 \\ =3(4)+5 \\ =12+5 \\ =17 \end{gathered}$

So the correct answer is f(x)=17