Answer:
x² + 9x + 20
Explanation:
f(x) = x² + 5x + 6
g(x) = x + 2
Now, let us find (f o g)(x)
(f o g)(x) = f(g(x))
= f(x+2)
= (x + 2)² + 5(x +2) + 6
{Identity used: (a + b)² = a² + 2ab +b²}
= x² + 2*x*2 + 2² +5*x +5*2 + 6
=x² + 4x + 4 + 5x + 10 + 6
= x² + 4x + 5x + 4 + 10 + 6
Combine like terms,
= x² + 9x + 20