展开-(10(sqrt(1985)-5))/(49)

解答

展开

- \frac{10 ( 1985 - 5 )}{49}

- \frac{10 1985}{49} + \frac{50}{49}

十进制

- 8.07210 \dots

求解步骤

- \frac{10 ( 1985 - 5 )}{49}

乘开

10 (1985 - 5) : 101985 - 50

= - \frac{10 1985 - 50}{49}

使用分式法则:

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

\frac{10 1985 - 50}{49} = - (\frac{10 1985}{49}) - (- \frac{50}{49})

= - (\frac{10 1985}{49}) - (- \frac{50}{49})

去除括号:

(a) = a, - (- a) = a

= - \frac{10 1985}{49} + \frac{50}{49}

e x p an d 3 b (a + b x (a + b x))

e x p an d 6 y + 3 - 2 (- 7 y - 5 = 5 (7 y - 1))

e x p an d \frac{ab + c}{ab}

e x p an d \frac{3 x + 18}{4 ( x ^{2} - 2 x - 4 )}

e x p an d \frac{6}{( s + 8 ) ( s - 4 )}