diketahui g(x)=ax+b. Tentukan nilai a dan b jika g(g(x))=16x-15.

jawqab

g(x) = ax + b
g (g(x)) =  16 x - 15
g(ax + b) = 16x - 15

a(ax +b) + b = 16x - 15
a²x + ab + b = 16x - 15
a²= 16
a= 4  atau a = - 4

ab + b = -15
b(a+1)= - 15
b = - 15/ (a + 1)

a= 4 --> b = -15/5  = -3
a = - 4 -> b = -15/-3=  5

(a,b)= (4, -3) , (-4, 5)