Rút gọn: -2x(x-3)^2 + (x + 2)(x - 1)(x + 1)
Giải thích
–2x(x-3)² + (x + 2)(x - 1)(x + 1)
= –2x(x2 – 6x + 9) + (x + 2)(x2 – 1)
= –2x3 + 12x2 – 18x + x3 – x – 2x2 + 2
= –x3 + 10x2 – 19x + 2
–2x(x-3)² + (x + 2)(x - 1)(x + 1)
= –2x(x2 – 6x + 9) + (x + 2)(x2 – 1)
= –2x3 + 12x2 – 18x + x3 – x – 2x2 + 2
= –x3 + 10x2 – 19x + 2