Question

If
f(x) = x2 + 2x + 9,
what is
f(x + 1)?

Answer 1

x² + 4x + 12

Explanation:

f(x) = x² + 2x + 9

f(x + 1) = (x + 1)² + 2(x + 1) + 9 = x² + 2x + 1 + 2x + 2 + 9 = x² + 4x + 12