Diketahui f(x) = (2x+5)2 dan g(x) = -5x+2 : a) (fog)(x); b) (fog)(-2);(gof)(x); d) (gof)(1)

Dik : f (x) = (2x+5)2 => (4x+10)
        g(x) = -5x + 2
Dit : a. (fog) (x) = ?
        b. (fog) (-2) = ?
        c. (gof) (x) = ?
        d. (gof) (1) =?
Peny :
a. (fog) (x) 
= f (-5x+2)
=4 (-5x+2)+10
=-20x + 8 + 10
=-20x + 18

b. (fog) (-2)
=> (fog) (x) = -20x + 18
=>  (fog) (-2) = -20 (-2) +18
                     = 40+18 = 58

c. (gof) (x)
= g ( 4x+10)
= -5 (4x+10) + 2
= -20x – 50 + 2
= -20x – 48

d. (gof) (1) = -20 (1) – 48 = -20-48 = -68