因式分解 x^3+2x^2-1

解答

因式分解

x^{3} + 2 x^{2} - 1

(x + 1) (x^{2} + x - 1)

求解步骤

x^{3} + 2 x^{2} - 1

使用有理根定理

= (x + 1) \frac{x ^{3} + 2 x ^{2} - 1}{x + 1}

\frac{x ^{3} + 2 x ^{2} - 1}{x + 1} = x^{2} + x - 1

= (x + 1) (x^{2} + x - 1)

f a c t or r^{7} - s^{7}

f a c t or 6 x^{2} - x - 5

8 = - \frac{2}{3} x

x^{2} = 5.44

3.8 z - 8.4 = 32.8 z + 4.4