Answer
True.
Work Step by Step
The given functions are
$f(x)=\sqrt x$ and $g(x)=2x-1$.
Plug $x=5$ into the second function.
$g(5)=2(5)-1$
$g(5)=10-1$
$g(5)=9$.
$(f\circ g)(5)=f(g(5))$
$(f\circ g)(5)=f(9)$
Plug $x=9$ into first function.
$(f\circ g)(5)=\sqrt 9$
$(f\circ g)(5)=3$.
Now plug $x=2$ into the second function.
$g(2)=2(2)-1$
$g(2)=4-1$
$g(2)=3$.
Hence, $(f\circ g)(5)=g(2)=3$.
