Diketahui f[invers](x)=8. Tentukan x jika: a. f(x)=3x-5 b. f(x)=5x+1

a. f(x) = 3(8)-5= 19
b. f(x) =5(8)+1=41

a) f(x) = 3x - 5
y = 3x - 5
(y+5)/3 = x
f^-1 (x) = (x+5)/3
8 = (x+5)/3
24 = x+5
x = 19

b) f(x) = 5x+1
y = 5x+1
(y-1)/5 = x
f^-1 (x) = (x-1)/5
8 = (x-1)/5
40 = x-1
x = 41

Semoga membantu,