Question

Which shows one way to determine the factors of x3 – 12x2 – 2x + 24 by grouping?

x(x2 – 12) + 2(x2 – 12)
x(x2 – 12) – 2(x2 – 12)
x2(x – 12) + 2(x – 12)
x2(x – 12) – 2(x – 12)

Answer 1

x^2(x − 12) − 2(x − 12).

Group as x^2(x − 12) − 2(x − 12) = (x^2 − 2)(x − 12), which expands to x^3 − 12x^2 − 2x + 24.