展开 (5(2+sqrt(2)))/2

解答

展开

\frac{5 ( 2 + 2 )}{2}

5 + \frac{5}{2}

十进制

8.53553 \dots

求解步骤

\frac{5 ( 2 + 2 )}{2}

乘开

5 (2 + 2) : 10 + 52

= \frac{10 + 5 2}{2}

使用分式法则:

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

\frac{10 + 5 2}{2} = \frac{10}{2} + \frac{5 2}{2}

= \frac{10}{2} + \frac{5 2}{2}

数字相除:

\frac{10}{2} = 5

= 5 + \frac{5 2}{2}

消掉

\frac{5 2}{2} : \frac{5}{2}

= 5 + \frac{5}{2}

\frac{d}{d t} ((x) (π - t))

e x p an d \frac{( - 2 x + 7 ) ( x + 1 )}{x - 3}

e x p an d 3 ((x - 3) (x + 2) (x - 4))

e x p an d \frac{( - 6 + n ) ( 6 + n )}{4}

e x p an d t esc a l o n (t - 1)