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信息发布者:
乘方
$(\frac{a}{b})^n=\frac{a^n}{b^n}$($b\neq0,$$n$是正整数)
从左往右
除法
乘法
乘法
乘方
乘除
A
B
$\frac{a^4}{9b^2}$
$-\frac{a - b}{a + b}$
解:$(\frac{2a^2b}{c})^3=\frac{(2a^2b)^3}{c^3}=\frac{2^3\times(a^2)^3\times b^3}{c^3}=\frac{8a^6b^3}{c^3}$
解:
$\begin{aligned}(\frac{y}{6x^2})^2\div(-\frac{y^2}{4x^2})^2&=\frac{y^2}{36x^4}\div\frac{y^4}{16x^4}\\&=\frac{y^2}{36x^4}\times\frac{16x^4}{y^4}\\&=\frac{16}{36y^2}\\&=\frac{4}{9y^2}\end{aligned}$
解:
$\begin{aligned}\frac{x - 3}{x + 4}\cdot\frac{x^2 - 16}{x^2 - 6x + 9}&=\frac{x - 3}{x + 4}\cdot\frac{(x + 4)(x - 4)}{(x - 3)^2}\\&=\frac{x - 4}{x - 3}\end{aligned}$
解:
$\begin{aligned}\frac{3x}{4x - 3}\div\frac{2}{16x^2 - 9}\cdot\frac{x}{4x + 3}&=\frac{3x}{4x - 3}\cdot\frac{(4x + 3)(4x - 3)}{2}\cdot\frac{x}{4x + 3}\\&=\frac{3x\cdot(4x + 3)(4x - 3)\cdot x}{(4x - 3)\cdot2\cdot(4x + 3)}\\&=\frac{3}{2}x^2\end{aligned}$