Question

sejam f(x)=x²-1 e g(x)=x+2 determine

a) f(g(x))

b)g(f(x))

c)f(g(2))

d)g(f(3))

Answer 1

a) f(g(x)) = f(x+2) = (x+2)² -1 =  x² + 4x + 4 - 1  =  x² + 4x + 3

b)g(f(x))  = g(x²-1) = x² -1 +2  = x² + 1

c)f(g(2))  = f(g(2)) = 2² + 4.2 + 3 = 4 + 8 + 3 = 15

d)g(f(3)) = g(f(3)) = 3² + 1 = 9 + 1 = 10