[tex]f(x) = x2 -3x dan \: g(x) = 2x + 1.mk \: (fog)(x) = [/tex] tolong y kak...

jawab

f(x) = x^2 - 3
g(x) = 2x + 1

fog(x) = f {gf(x)}= f(2x+1)
fog(x)= (2x+1)^2 - 3  
fog(x) =  4x^2 +4x +1 - 3
fog(x) = 4x^2 + 4x -  2