Jika f(x) = x² + 7x dan g(x) = 4x + 1 maka (fog)(-1) =

f(x) = x² + 7x
g(x) = 4x + 1

Ditanya (fog)(-1)


Jawaban :

(f o g) (x) :
= f(4x + 1)
= (4x + 1)² + 7(4x + 1)
= 16x² + 8x + 1 + 28x + 7
= 16x² + 36x + 8

(f o g) (-1) :
= 16x² + 36x + 8
= 16(-1)² + 36(-1) + 8
= 16 - 36 + 8
= -12✔