Dik:f(x) =x+4 dan g(x) =2x Tentukan:(fog)-1 dan (gof)-1

f(x) = x+4
g(x)= 2x
dit : fog(-1) =..?
gof(-1)=..?
jwb : fog(-1) = 2x+4
=2(-1)+4
= -2+4
= 2
gof(-1) =2(x+4)
=2x+8
=2(-1)+8
=-2+8
= 6