contestada

(fog)(x) If ​f(x)=x^2- 4 and ​g(x)=x^2 + 2 x​,

f(g(x))= f(x^2+2x)
(x^2+2x)^2-4
(x^2+2x)(x^2+2x)-4
(x^4+2x^3+5x+4x^2)-4
x^4+2x^3+4x^2+5x-4


what am I doing wrong ???

Respuesta :

Answer:

You went wrong on the 4th line  while expanding the parentheses.

See below.

Step-by-step explanation:

(x^2 + 2x)(x^2 + 2x) - 4

= x^4 + 2x^3 + 2x^3 + 4x^2 - 4

= x^4 + 4x^3 + 4x^2 - 4. (answer).

Otras preguntas