因式分解 e^2-81

解答

因式分解

e^{2} - 81

(e + 9) (e - 9)

求解步骤

e^{2} - 81

将

81

改写为

9^{2}

= e^{2} - 9^{2}

使用平方差公式:

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

e^{2} - 9^{2} = (e + 9) (e - 9)

= (e + 9) (e - 9)

f a c t or e^{j w} - e^{- j w}

f (E) = E

f a c t or i s in g x^{2} - 5 x + 25

s im pl i f y (F_{(13)})^{(2)} - 4 F_{(20)}

f a c t or 5 + 7 (a + 1) - 6 (a + 1)^{2}