展开-(2(8+sqrt(19)))/3

解答

展开

- \frac{2 ( 8 + 19 )}{3}

- \frac{16}{3} - \frac{2 19}{3}

十进制

- 8.23926 \dots

求解步骤

- \frac{2 ( 8 + 19 )}{3}

乘开

2 (8 + 19) : 16 + 219

= - \frac{16 + 2 19}{3}

使用分式法则:

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

\frac{16 + 2 19}{3} = - (\frac{16}{3}) - (\frac{2 19}{3})

= - (\frac{16}{3}) - (\frac{2 19}{3})

去除括号:

(a) = a

= - \frac{16}{3} - \frac{2 19}{3}

e x p an d (4 x^{3} - 6 x y^{2}) d x

e x p an d (x + Δ x)^{2} - 4 (x + Δ x) + 5

e x p an d (- 3, - 5, - 1) x (- 4, 5, 7)

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

e x p an d 2 - 6 (5 + 2 [3 + 5 (8 - 7 \cdot, 8)])