展开 ((x+1)(x-10))/(80)

解答

展开

\frac{( x + 1 ) ( x - 10 )}{80}

\frac{x ^{2}}{80} - \frac{9 x}{80} - \frac{1}{8}

求解步骤

\frac{( x + 1 ) ( x - 10 )}{80}

乘开

(x + 1) (x - 10) : x^{2} - 9 x - 10

= \frac{x ^{2} - 9 x - 10}{80}

使用分式法则:

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

\frac{x ^{2} - 9 x - 10}{80} = \frac{x ^{2}}{80} - \frac{9 x}{80} - \frac{10}{80}

= \frac{x ^{2}}{80} - \frac{9 x}{80} - \frac{10}{80}

消掉

\frac{10}{80} : \frac{1}{8}

= \frac{x ^{2}}{80} - \frac{9 x}{80} - \frac{1}{8}

e x p an d \frac{1 - x ^{2} + x}{( 2 x ^{2} + 3 ) ( x ^{2} + 2 )}

e x p an d \frac{s ^{2} + 3 s + 4 b}{( s + 2 ) ^{3} ( s + 1 ) ( s + a )}

e x p an d e^{9 (a - jω)}

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

e x p an d \frac{( x + 10 ) ( 2 x - 1 )}{( x + 2 ) ( x - 1 )}