jika diket f(x) =x² 2x+1 dan g(x) = x-1 serta (f•g)(x) = 4, maka nilai x adalh

fog(x)=f(g(x)
fog(x)=x-1
=x^2+2x+1
=(x-1)^2+2(x-1)+1
=x^2(-2x)+1+2x-1+1
=x^2+1
fog(x)=4
x^2+1=4
x^2=4-1
x= akar kuadrat 3