化简 (2x^3+4x^2-5)-(4x^3-x^2+3x+12)

解答

化简

(2 x^{3} + 4 x^{2} - 5) - (4 x^{3} - x^{2} + 3 x + 12)

- 2 x^{3} + 5 x^{2} - 3 x - 17

求解步骤

(2 x^{3} + 4 x^{2} - 5) - (4 x^{3} - x^{2} + 3 x + 12)

使用法则:

(a) = a

(2 x^{3} + 4 x^{2} - 5) = 2 x^{3} + 4 x^{2} - 5

= 2 x^{3} + 4 x^{2} - 5 - (4 x^{3} - x^{2} + 3 x + 12)

使用分配律:

- (a - b) = - a + b

- (4 x^{3} - x^{2} + 3 x + 12) = - 4 x^{3} + x^{2} - 3 x - 12

= 2 x^{3} + 4 x^{2} - 5 - 4 x^{3} + x^{2} - 3 x - 12

对同类项分组

= 2 x^{3} - 4 x^{3} + 4 x^{2} + x^{2} - 3 x - 5 - 12

r a t i o na l i ze \frac{2}{3}

e x p an d (6 + x) (6 - x)

e x p an d (8 x - 3)^{2}

s im pl i f y \frac{v ^{3} + 11 v ^{2} + 18 v}{v ^{2} + v - 2}

s im pl i f y \frac{x + 8}{x ^{2} - 4 x + 4} + \frac{3 x - 2}{x ^{2} - 4}