展开 (20e^{-4x})/(x(x^2+4x+20))

解答

展开

\frac{20 e ^{- 4 x}}{x ( x ^{2} + 4 x + 20 )}

\frac{20 e ^{- 4 x}}{x ^{3} + 4 x ^{2} + 20 x}

求解步骤

\frac{20 e ^{- 4 x}}{x ( x ^{2} + 4 x + 20 )}

乘开

x (x^{2} + 4 x + 20) : x^{3} + 4 x^{2} + 20 x

= \frac{20 e ^{- 4 x}}{x ^{3} + 4 x ^{2} + 20 x}

e x p an d - \frac{3 ( 4 x ^{3} + 6 x ^{2} h + 4 x h ^{2} + h ^{3} )}{x ^{4} ( x + h ) ^{4}}

e x p an d \frac{1}{( a - 2 x ) ^{2} ( b - x )}

e x p an d \frac{12 x}{( x ^{2} + 6 ) ^{2}}

e x p an d - \frac{2 x}{( x ^{2} - 4 ) ^{2}}

s im pl i f y (3 + 1 - y^{2})^{2}