展开 ((x+1)(2x+1))/6

解答

展开

\frac{( x + 1 ) ( 2 x + 1 )}{6}

\frac{x ^{2}}{3} + \frac{x}{2} + \frac{1}{6}

求解步骤

\frac{( x + 1 ) ( 2 x + 1 )}{6}

乘开

(x + 1) (2 x + 1) : 2 x^{2} + 3 x + 1

= \frac{2 x ^{2} + 3 x + 1}{6}

使用分式法则:

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

\frac{2 x ^{2} + 3 x + 1}{6} = \frac{2 x ^{2}}{6} + \frac{3 x}{6} + \frac{1}{6}

= \frac{2 x ^{2}}{6} + \frac{3 x}{6} + \frac{1}{6}

消掉

\frac{2 x ^{2}}{6} : \frac{x ^{2}}{3}

= \frac{x ^{2}}{3} + \frac{3 x}{6} + \frac{1}{6}

消掉

\frac{3 x}{6} : \frac{x}{2}

= \frac{x ^{2}}{3} + \frac{x}{2} + \frac{1}{6}

e x p an d (5 cos (x) + 4 sin (x)) d x

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

e x p an d (x^{2} + 3 x - 2) (ln (x))

e x p an d (1 + 2 x - x^{2})^{6}

e x p an d \frac{( - 5 ) x - 1}{5}