展开 ((2+5y)^2)/4

解答

展开

\frac{( 2 + 5 y ) ^{2}}{4}

\frac{25 y ^{2}}{4} + 5 y + 1

求解步骤

\frac{( 2 + 5 y ) ^{2}}{4}

(2 + 5 y)^{2} = 4 + 20 y + 25 y^{2}

= \frac{4 + 20 y + 25 y ^{2}}{4}

使用分式法则:

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

\frac{4 + 20 y + 25 y ^{2}}{4} = \frac{4}{4} + \frac{20 y}{4} + \frac{25 y ^{2}}{4}

= \frac{4}{4} + \frac{20 y}{4} + \frac{25 y ^{2}}{4}

使用法则

\frac{a}{a} = 1

\frac{4}{4} = 1

= 1 + \frac{20 y}{4} + \frac{25 y ^{2}}{4}

数字相除:

\frac{20}{4} = 5

= 1 + 5 y + \frac{25 y ^{2}}{4}

改写为标准形式

= \frac{25 y ^{2}}{4} + 5 y + 1

e x p an d (x + 1.5) \cdot (x + 0, 3) \cdot (x - 2, 7)

e x p an d (1 - 22)^{4}

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

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

e x p an d 3 ((x + 3) (x - 2) (x - 5))