Question

31. (3x2 + 5x - 7)(x - 1) - (x2 - 2x +3)(x + 4)​

Answer 1

2x^3-7x-5(is the correct answer)

Answer 2

Answer:

2x³ - 7x - 5

Step-by-step explanation:

= (3x² + 5x - 7)(x - 1) - (x² - 2x +3)(x + 4)

= 3x³-3x²+5x²-5x-7x+7- (x²-2x+3)(x+4)

= 3x³-3x²+5x-7x+7- (x³+4x²-2x²-8x+3x+12)

= 3x³-3x²+5x-7x+7- (x³+2x²-8x+3x+12)

= 3x³-3x²+5x²-5x-7x+7- (x³+2x²-5x+12)

= 2x³-3x²+5x²-7x+7-2x²-12

= 2x³+0-7x-5

= 2x³-7x-5

$\boxed{→ 2x³ - 7x - 5}$