第20页 - 江苏版实验班提优训练数学七年级上下册答案

6a³b²

27

$2.3×10^{-7}$

3

11

25

7

1753

$ \begin{aligned}解：原式&=9+1+4 \\ &=14. \\ \end{aligned}$

$ \begin{aligned}解：原式&=a⁶·a¹º÷a¹⁶ \\ &=1. \\ \end{aligned}$

$ \begin{aligned}解：原式&=(a+2b)(2a-b-2a) \\ &=-ab-2b². \\ \end{aligned}$

$ \begin{aligned} 解：原式&=[(2x-3y)(2x+3y)]² \\ &=(4x²-9y²)² \\ &=16x⁴-72x²y²+81y⁴. \\ \end{aligned}$

$ \begin{aligned} 解：原式&=x(x²-2xy+y²) \\ &=x(x-y)². \\ \end{aligned}$

$ \begin{aligned}解：原式&=3a(x-y)+6b(x-y) \\ &=3(x-y)(a+2b). \\ \end{aligned}$