因式分解 a^4-5a^2-36

解答

因式分解

a^{4} - 5 a^{2} - 36

(a^{2} + 4) (a + 3) (a - 3)

求解步骤

a^{4} - 5 a^{2} - 36

令

u = a^{2}

= u^{2} - 5 u - 36

因式分解

u^{2} - 5 u - 36 : (u + 4) (u - 9)

= (u + 4) (u - 9)

u = a^{2}

代回

= (a^{2} + 4) (a^{2} - 9)

因式分解

a^{2} - 9 : (a + 3) (a - 3)

= (a^{2} + 4) (a + 3) (a - 3)

\frac{2}{5} x = - \frac{1}{10}

\frac{3 x - 2}{12} - \frac{1}{6} = \frac{1}{6}

s im pl i f y \frac{8}{1 - 3}

f a c t or kn - mn - n^{2} + mk

s im pl i f y \frac{1}{1.2 \cdot 1 0 ^{- 5}} + \frac{1}{6 \cdot 1 0 ^{- 6}}