展开 (15(x-2)^2)/2

解答

展开

\frac{15 ( x - 2 ) ^{2}}{2}

\frac{15 x ^{2}}{2} - 30 x + 30

求解步骤

\frac{15 ( x - 2 ) ^{2}}{2}

(x - 2)^{2} = x^{2} - 4 x + 4

= \frac{15 ( x ^{2} - 4 x + 4 )}{2}

乘开

15 (x^{2} - 4 x + 4) : 15 x^{2} - 60 x + 60

= \frac{15 x ^{2} - 60 x + 60}{2}

使用分式法则:

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

\frac{15 x ^{2} - 60 x + 60}{2} = \frac{15 x ^{2}}{2} - \frac{60 x}{2} + \frac{60}{2}

= \frac{15 x ^{2}}{2} - \frac{60 x}{2} + \frac{60}{2}

数字相除:

\frac{60}{2} = 30

= \frac{15 x ^{2}}{2} - 30 x + 30

s im pl i f y δ (x - 5)

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