展开 (10(12-sqrt(15)))/3

解答

展开

\frac{10 ( 12 - 15 )}{3}

40 - \frac{10 5}{3}

十进制

27.09005 \dots

求解步骤

\frac{10 ( 12 - 15 )}{3}

乘开

10 (12 - 15) : 120 - 1015

= \frac{120 - 10 15}{3}

使用分式法则:

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

\frac{120 - 10 15}{3} = \frac{120}{3} - \frac{10 15}{3}

= \frac{120}{3} - \frac{10 15}{3}

数字相除:

\frac{120}{3} = 40

= 40 - \frac{10 15}{3}

消掉

\frac{10 15}{3} : \frac{10 5}{3}

= 40 - \frac{10 5}{3}

e x p an d a cos (b (x - c)) + d

e x p an d \frac{( 2 ( 1 - cot ( 2 x ) ) ( sec ^{2} ( 2 x ) ) - 2 ( csc ^{2} ( 2 x ) ) ( tan ( 2 x ) ) )}{( 1 - cot ( 2 x ) ) ^{2}}

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

e x p an d \frac{10 x ( - 5 x ^{3} + y ^{3} )}{y ^{5}}

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