[tex]\huge {\boxed {\tt{Solution :}}}[/tex]
Putting value we get :
[tex]\sf{ : \implies{f(x) = 2x^2 + 1 }} \\ \\ \sf{ : \implies{f(3) = 2 \times (3)^2 + 1 }} \\ \\ \sf{ : \implies{f(3) = 2 \times 9+1 }} \\ \\ \sf{ : \implies{f(3) =1 8 +1 }} \\ \\ :\implies{\boxed{\tt{f(3) =19}}}[/tex]
[tex]\bf {\therefore{f(3) =19}}[/tex]
[tex]\rule {307}{2}[/tex]
