Step-by-step explanation:
a) fg(x) = f(x²-1) = 2(x²-1) + 3
= 2x² + 1
b) gf(x) = (2x+3)² - 1
= 4x² + 12x + 9 - 1
= 4x² + 12x + 8
c) fg(2) replace the value in a)
fg(2) = 2(2²) + 1
= 9
