g) x^4 – 16 = (x^2)^2 ‒ 4^2
g) x4 – 16 = (x2)2 ‒ 42
g) x4 – 16 = (x2)2 ‒ 42
= (x2 ‒ 4)(x2 + 4)
= (x2 ‒ 22)(x2 + 4)
= (x + 2)(x ‒ 2)(x2 + 4).