展开 (x(10-x^2))/2

解答

展开

\frac{x ( 10 - x ^{2} )}{2}

- \frac{x ^{3}}{2} + 5 x

求解步骤

\frac{x ( 10 - x ^{2} )}{2}

乘开

x (10 - x^{2}) : 10 x - x^{3}

= \frac{10 x - x ^{3}}{2}

使用分式法则:

\frac{a \pm b}{c} = \frac{a}{c} \pm \frac{b}{c}

\frac{10 x - x ^{3}}{2} = \frac{10 x}{2} - \frac{x ^{3}}{2}

= \frac{10 x}{2} - \frac{x ^{3}}{2}

数字相除:

\frac{10}{2} = 5

= 5 x - \frac{x ^{3}}{2}

改写为标准形式

= - \frac{x ^{3}}{2} + 5 x

e x p an d \frac{x A + B + 4 A}{( x - 1 ) ( x - 3 )}

e x p an d \frac{1}{2 ( x + 2 )}

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

e x p an d \frac{x + 5}{x ( x + 11 )}

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