展开 (2(2n-2x))/(n^2)

解答

展开

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

\frac{4}{n} - \frac{4 x}{n ^{2}}

求解步骤

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

乘开

2 (2 n - 2 x) : 4 n - 4 x

= \frac{4 n - 4 x}{n ^{2}}

使用分式法则:

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

\frac{4 n - 4 x}{n ^{2}} = \frac{4 n}{n ^{2}} - \frac{4 x}{n ^{2}}

= \frac{4 n}{n ^{2}} - \frac{4 x}{n ^{2}}

消掉

\frac{4 n}{n ^{2}} : \frac{4}{n}

= \frac{4}{n} - \frac{4 x}{n ^{2}}

e x p an d - 1 (3 x + 3 y = 24)

e x p an d \frac{2}{x ( x + 5 a ) ( x + 6 a )}

e x p an d (2 x^{2} t - 2 x^{3}) d t

e x p an d (x^{2} - 2 u^{2} x^{2}) d x

e x p an d \frac{1 - e ^{- s}}{s ( s ^{2} - 4 s - 45 )}