fungsi f(×) dan g(×) didefinisikan dengan f(×)=ײ, g(×)=1-2×, dan (fog)(a)=25. Nilai a sama dengan...

(fog)(a)= f (g(a)) = f ( 1 - 2a) = ( 1 - 2a)^2 = 25
1 - 2a = +- akar 25
1 - 2a = +- 5
-2a = -1 +- 5
(+) -2a = 4
a = 4/-2 = -2
(-) -2a = -6
a = -6/-2 = 3