jika f(x) = 2x^2 +5 x dan g(x) =1/x maka (fog)(2)=....?

f (g(x)) 
= f (1/x)
=(2*1/x)^2 + 5(1/x) 
=(2/x)^2 + 5/x
(f.g)(x)=4/x^2 + 5/x

(f.g)(2) = 4/(2)^2 + 5/2
            = 4/4 + 5/2
            = 1 + 5/2
            = 2/2 + 5/2
            = 7/2