1. Diketahui f(x) = 2x+1 (Gof)(x) = 2x²+6x+2 Tentukan g(3)... 2. Diketahui f(x) = 2x+1 per x-3 ; x tidak sama dengan 0 Tentukan a. F pangkat -1(x) b. F pangkat

1) f (x) = 2x +1
gof(x) = 2x^2 + 6x + 2
g { f (x) } = 2x^2 + 6x + 2
g ( 2x+1) = 2x^2+ 6x +2
g (2x+1) = 1/2(2x+1)^2+ 4x + 3/2
g (2x+1) = 1/2(2x+1)^2 + 2(2x+1) -1/2
g (x) = 1/2x^2 +2x -1/2
g (3) = 1/2(3)^2 +2.3 -1/2
= 9/2 +6 -1/2
= 10
2)f (x) = (2x+1)/(x-3)
y = (2x+1)/(x-3)
(x-3)y = 2x +1
xy -3y = 2x + 1
xy -2x = 3y +1
(y -2)x = 3y +1
x = (3y +1)/(y -2)
f-1(x) = (3x +1)/(x -2)
f-1(9) = (3.9 +1)/(9-2)
= 28/7
= 4