什么是 (2/−3) 的乘法逆？
对于数学中不同数量的表示，我们使用诸如 20 个苹果、10 个香蕉等数字。但是对于这些数字的计算，我们需要数学运算。以下是不同类型的主要数学运算：
- 加法：用“+”号表示。它用于不同数量或数字组的总和。
- 减法：用“-”号表示。当从一组数字或数量中取出一些数字或数量时使用它。
- 乘法：用“×”号表示。它是加法的扩展形式。当添加相同类型的数量或一组数字时使用它。
- 除法：用“÷”号表示。当相同类型的项目平均分配到不同位置时使用它。
什么是乘法逆？
If the multiplication of two rational numbers gives 1 as result, then these two rational numbers are termed as the multiplicative inverse of each other. In other terms, we can say that the reciprocal of numbers is the multiplicative inverse of each other. For the calculation of multiplicative inverse of rational number usually, numerator and denominator got exchanged along with the sign and for the calculation of multiplicative inverse of a number, divide 1 by the number.
如何找到乘法逆？
假设有理数是“a/b”，其中 b 不等于 0，我们必须找出该数的乘法倒数。
步骤1：交换分子和分母以及它们的符号，即'a'被'b'改变，'b'被'a'改变。所以乘法逆元是'b/a'。
第 2 步：对于数字“a”的乘法逆元，将 1 除以该数字及其符号。
'a' 的乘法逆元 = 1/a。
(2/-3) 的乘法逆元是什么？
解决方案：
Compare (2/-3) with a/b.
a = 2, b = -3
Now change the numerator with denominator and denominator with numerator along with their sign.
i.e. (b/a)
Multiplicative inverse = (-3/2)
The multiplicative inverse of (2/-3) is (-3/2).
类似问题
问题 1 ：求 (-3/7) 的乘法逆元。
解决方案：
Compare (-3/7) with (a/b).
We got, a = -3 and b = 7
Exchange numerator and denominator with their sign.
Multiplicative inverse = (7/-3)
The multiplicative inverse of (-3/7) is (7/-3).
问题 2：应将 (-5) 乘以哪个数得到答案 1？
解决方案：
Basically, we have to find out the multiplicative inverse of (-5). Because when we multiply a number with its multiplicative inverse, we got the answer 1.
For the calculation of multiplicative inverse of (-5), divide 1 by (-5).
So, the multiplicative inverse of (-5) is (1/-5).