展开 (2.5(s+7.2)(s+6.4))/s

解答

展开

\frac{2.5 ( s + 7.2 ) ( s + 6.4 )}{s}

2.5 s + 34 + \frac{115.2}{s}

求解步骤

\frac{2.5 ( s + 7.2 ) ( s + 6.4 )}{s}

乘开

2.5 (s + 7.2) (s + 6.4) : 2.5 s^{2} + 34 s + 115.2

= \frac{2.5 s ^{2} + 34 s + 115.2}{s}

使用分式法则:

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

\frac{2.5 s ^{2} + 34 s + 115.2}{s} = \frac{2.5 s ^{2}}{s} + \frac{34 s}{s} + \frac{115.2}{s}

= \frac{2.5 s ^{2}}{s} + \frac{34 s}{s} + \frac{115.2}{s}

消掉

\frac{2.5 s ^{2}}{s} : 2.5 s

= 2.5 s + \frac{34 s}{s} + \frac{115.2}{s}

消掉

\frac{34 s}{s} : 34

= 2.5 s + 34 + \frac{115.2}{s}

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