g(x)=x+1/x-3 dan fog(x)=2x+3 tentukan g(x)

Boom...

f(x) = (x + 1)/(x - 3)

f(g(x)) = 2x + 3
f(a) = 2x + 3
(a + 1)/(a - 3) = 2x + 3
a + 1 = (a - 3)(2x + 3)
a + 1 = 2ax - 6x + 3a - 9
a - 2ax - 3a = - 1 - 9 - 6x
a(-2 - 2x) = (-10 - 6x)
a = (-10 - 6x)/(-2 - 2x)
a = (-2)(5 + 3x) / (-2)(1 + x)
a = (5 + 3x)/(1 + x)

g(x) = a = (5 + 3x)/(1 + x)