如何表示为具有正指数的有理数的幂?
指数和幂用于以简化的方式显示非常大的数字或非常小的数字。例如,如果我们必须以简单的方式显示 2 × 2 × 2 × 2,那么我们可以将其写为 2 4 ,其中 2 是底数,4 是指数。整个表达式 24 被称为幂。
Power is a value or an expression that represents repeated multiplication of the same number or factor. Number of times the base is multiplied to itself is the value of the exponent.
举些例子:
3 2 = 3 升幂 2 = 3 × 3 = 9
4 3 = 4 升幂 3 = 4 × 4 × 4 = 64
一个数的指数表示该数与自身相乘的次数。例如- 2 与自身相乘 n 次:
2 × 2 × 2 × 2 × …..n times = 2n
上述表达式 2 n被称为 2 的 n 次幂。因此,指数也称为幂,有时也称为指数。
指数的一般形式
指数表示一个数字应该与自身相乘多少次才能得到结果。因此,任何数字“b”的幂“p”都可以表示为:
bp = {b × b × b × b × …. × b} p times
这里b是任意数,p是自然数。
- b p也称为 b 的 p 次方。
- “b”是底数,“p”是指数或指数或幂。
- 'b' 乘以 'p' 倍,因此求幂是重复乘法的简写方法。
指数定律
让“b”是任何数字或整数(正数或负数),“p1”、“p2”是正整数,表示基数的幂。
乘法定律
它指出具有相同底数和不同幂的两个指数的乘积等于将底数提升为两个幂或整数的和。
bp1 × bp2 = b(p1+p2)
分割法
它指出,如果将具有相同底数和不同幂的两个指数相除,则结果将以两个幂之间的差为基数。
bp1 ÷ bp2 = bp1/ bp2 = b(p1-p2)
负指数定律
如果底有一个负幂,那么它可以被转换成它的倒数,但它是底的正幂或整数。
b-p = 1/bp
指数的基本规则
为了求解指数表达式以及其他数学运算,为指数定义了一些基本规则,例如,如果有两个指数的乘积,则可以简化以使计算更容易,称为乘积规则,让我们看一下指数的一些基本规则,
Product Rule ⇢ an × am = an + m
Quotient Rule ⇢ an / am = an – m
Power Rule ⇢ (an)m = an × m or m√an = an/m
Negative Exponent Rule ⇢ a-m = 1/am
Zero Rule ⇢ a0 = 1
One Rule ⇢ a1 = a
如何表示为具有正指数的有理数的幂?
解决方案:
Rational numbers are of the form p/q, where p and q are integers and q ≠ 0. Because of the underlying structure of numbers, p/q form, most individuals find it difficult to distinguish between fractions and rational numbers.
When a rational number is divided, the output is in decimal form, which can be either ending or repeating. 3, 4, 5, and so on are some examples of rational numbers as they can be expressed in fraction form as 3/1, 4/1, and 5/1.
Now for the answer of the Question, consider the following example:
{(-3/5)2 × (-3/5)4}3
[(-3/5)2 × (-3/5)4]3
= [(-3/5)2+4]3
= [(-3/5)6]3
= (-3/5)6×3
= (-3/5)18
类似问题
问题 1:求解 (2 2 ) × (7 2 )
解决方案:
Here when bases are different and powers are same
So as per the product rule we can write as an × bn = (a × b)n.
So 22 × 72
= (2 × 7)2
= 142
= 196
问题 2:求 5 -2 × 1/5 2的值。
解决方案:
Here we have 5-2 × 1/5-2
We will use Negative Exponent Rule ⇢ a-m = 1/am
So we can write above eq. as
5-2 × 1/52
= 5-2 × 5-2
= 5-2 + (-2)
= 5-2 – 2
= 5-4
= 1/54
问题 3:化简 (5/8) -7 × (8/5) -5
解决方案:
(5/8)-7 × (8/5)-5
= 1/(5/8)7 × (8/5)-5 {Negative Exponent Rule ⇢ a-m = 1/am}
= (8/5)7 × (8/5)-5
= (8/5)7 + (-5) {Product Rule ⇢ an × am = an + m}
= (8/5)2
= 64/25