题目
(1) 10^2 times 10^7;(2) (-2^2)^3 + (-2^3)^2;(3) ((x^2 cdot x^m)^3)/(x^2m);(4) (sqrt[4](x^3))/(x);(5) (-5)^2 times ((1)/(3))^-1;(6) (e^2)^3 cdot (e^3)^2;(7) (-(1)/(3) x^m+1 y^-n) cdot (-(1)/(3) x^2-m y^n-1);(8) (x-y)^2 cdot (x-y)^3 - (x-y)^4 cdot (y-x);(9) 若 2^m = 3, 2^n = 2, 则 2^3n-m = _____;
(1) $10^2 \times 10^7$; (2) $(-2^2)^3 + (-2^3)^2$; (3) $\frac{(x^2 \cdot x^m)^3}{x^{2m}}$; (4) $\frac{\sqrt[4]{x^3}}{x}$; (5) $(-5)^2 \times \left(\frac{1}{3}\right)^{-1}$; (6) $(e^2)^3 \cdot (e^3)^2$; (7) $\left(-\frac{1}{3} x^{m+1} y^{-n}\right) \cdot \left(-\frac{1}{3} x^{2-m} y^{n-1}\right)$; (8) $(x-y)^2 \cdot (x-y)^3 - (x-y)^4 \cdot (y-x)$; (9) 若 $2^m = 3$, $2^n = 2$, 则 $2^{3n-m} = \_\_\_\_\_$;
题目解答
答案
我们来逐题分析并解答这些题目。
---
### **(1) $10^2 \times 10^7$**
**解题过程:**
根据幂的乘法法则:
$$
a^m \times a^n = a^{m+n}
$$
所以:
$$
10^2 \times 10^7 = 10^{2+7} = 10^9
$$
**答案:**
$$
\boxed{10^9}
$$
---
### **(2) $(-2^2)^3 + (-2^3)^2$**
**解题过程:**
注意运算顺序:
- $-2^2 = -(2^2) = -4$,所以 $(-2^2)^3 = (-4)^3 = -64$
- $-2^3 = -(2^3) = -8$,所以 $(-2^3)^2 = (-8)^2 = 64$
所以:
$$
(-2^2)^3 + (-2^3)^2 = -64 + 64 = 0
$$
**答案:**
$$
\boxed{0}
$$
---
### **(3) $\frac{(x^2 \cdot x^m)^3}{x^{2m}}$**
**解题过程:**
先计算分子:
$$
x^2 \cdot x^m = x^{2+m} \Rightarrow (x^{2+m})^3 = x^{3(2+m)} = x^{6+3m}
$$
分母是 $x^{2m}$,所以:
$$
\frac{x^{6+3m}}{x^{2m}} = x^{(6+3m)-2m} = x^{6+m}
$$
**答案:**
$$
\boxed{x^{6+m}}
$$
---
### **(4) $\frac{\sqrt[4]{x^3}}{x}$**
**解题过程:**
$$
\sqrt[4]{x^3} = x^{3/4}
$$
所以:
$$
\frac{x^{3/4}}{x} = x^{3/4 - 1} = x^{-1/4}
$$
**答案:**
$$
\boxed{x^{-1/4}}
$$
---
### **(5) $(-5)^2 \times \left(\frac{1}{3}\right)^{-1}$**
**解题过程:**
- $(-5)^2 = 25$
- $\left(\frac{1}{3}\right)^{-1} = 3$
所以:
$$
25 \times 3 = 75
$$
**答案:**
$$
\boxed{75}
$$
---
### **(6) $(e^2)^3 \cdot (e^3)^2$**
**解题过程:**
- $(e^2)^3 = e^{2 \times 3} = e^6$
- $(e^3)^2 = e^{3 \times 2} = e^6$
所以:
$$
e^6 \cdot e^6 = e^{6+6} = e^{12}
$$
**答案:**
$$
\boxed{e^{12}}
$$
---
### **(7) $\left(-\frac{1}{3} x^{m+1} y^{-n}\right) \cdot \left(-\frac{1}{3} x^{2-m} y^{n-1}\right)$**
**解题过程:**
先处理系数:
$$
\left(-\frac{1}{3}\right) \cdot \left(-\frac{1}{3}\right) = \frac{1}{9}
$$
再处理幂的乘法:
- $x^{m+1} \cdot x^{2-m} = x^{(m+1)+(2-m)} = x^3$
- $y^{-n} \cdot y^{n-1} = y^{-n + (n-1)} = y^{-1}$
所以结果是:
$$
\frac{1}{9} x^3 y^{-1} = \frac{x^3}{9y}
$$
**答案:**
$$
\boxed{\frac{x^3}{9y}}
$$
---
### **(8) $(x-y)^2 \cdot (x-y)^3 - (x-y)^4 \cdot (y-x)$**
**解题过程:**
先看第一部分:
$$
(x-y)^2 \cdot (x-y)^3 = (x-y)^{2+3} = (x-y)^5
$$
第二部分:
$$
(x-y)^4 \cdot (y-x) = (x-y)^4 \cdot (-1)(x-y) = - (x-y)^5
$$
所以整个式子变为:
$$
(x-y)^5 - (x-y)^5 = 0
$$
**答案:**
$$
\boxed{0}
$$
---
### **(9) 若 $2^m = 3$, $2^n = 2$, 则 $2^{3n - m} = \_\_\_\_\_$**
**解题过程:**
已知:
- $2^n = 2 \Rightarrow n = 1$
- $2^m = 3 \Rightarrow m = \log_2 3$
所以:
$$
2^{3n - m} = 2^{3 \cdot 1 - \log_2 3} = 2^{3 - \log_2 3}
$$
利用对数性质:
$$
2^{3 - \log_2 3} = \frac{2^3}{2^{\log_2 3}} = \frac{8}{3}
$$
**答案:**
$$
\boxed{\frac{8}{3}}
$$
---
### **总结答案:**
1. $10^9$
2. $0$
3. $x^{6+m}$
4. $x^{-1/4}$
5. $75$
6. $e^{12}$
7. $\frac{x^3}{9y}$
8. $0$
9. $\frac{8}{3}$