Exponent Rules and Examples

An exponent or otherwise called power is a superscript over a base number that tells how many times you multiply that number by itself. It is a short version of repeated multiplication that makes writing equations simpler.

Exponent Rules

Zero Rule–a0 = 1

Product Rule-am x an = am+n

Quotient Rule-am/an = am-n

Power of a Product–(ab)m = ambm

Power of a Quotient–(a/b)m = am/bm

Power of a Power–(am)n = amn

Negative Exponent–a-m = 1/am

Fractional Exponent–am/n = (n√a)m

Check out 1 to the power of 94

Exponent Rules and Examples

Reading and Writing Exponents

For instance, 53 = (5)(5)(5) = 125. In this example, the number 5 is the base and the number 3 is the exponent (power). You can read the expression 53 as “five raised to the power of three” or “five raised to the third power.” However, a number raised to the power of 3 is typically read as “cubed”. Accordingly, 53 is “five cubed.” A number raised to the power of 2 is “squared.”

Many times, exponents combine with algebra. For example, here is an extended form and exponential form of an equation using x and y:

(x)(x)(x)(y)(y) = x3y2

Exponent Rules and Examples

Exponents facilitate writing very small or extremely large numbers. This is the reason why they find use in scientific notation. Understanding the rules for exponents makes working with them much more effortless.

Addition and Subtraction

Only when the base and exponent of the terms are the same you can add and subtract numbers with exponents. For instance:

n3 + 3n3 = 4n3

6a4 – 2a4 = 4a4

2x3y2 + 4x3y2 = 6x3y2

Zero Exponent Rule

The practical exponent rule is that any non-zero number raised to the zero power equals 1:

a0 = 1

So, no matter how complex the base is, if you raise it to zero power, it equals 1. For instance:

(62x5y3)0 = 1

Understanding this rule can save you a lot of pointless calculations!

Yet, if the base is 0, matters become complex. 00 has an indeterminate form.

Product Rule and Quotient Rule

Keep the base and add the exponents when you multiply exponents with the same base:

aman = am+n

(53)(52) = 53+2 = 55

Likewise, divide exponents with the same base by holding the base and subtracting the exponents:

am/an = am-n

53/52 = 53-2 = 51 = 5

x-3/x2 = x(-3-2) = x-5

Power of a Product

Distributing the exponent to each base is another way of expressing a base multiplied by an exponent:

(ab)m = ambm

(3×2)2 = (32)(22) = 9×4 = 36

(x2y2)3 = x6y6

Power of a Quotient

Distribution functions when dividing numbers, as well. Distribute the exponent to all values in the brackets:

(a/b)m = am/bm

(4/2)2 = 42/22 = 16/4 = 4

(4x3/5y4)2 = 42x6/52y8 = 16x6/25y8

Power of a Power Exponent Rule

Keep the base and multiply the exponents together when raising a power by another power:

(am)n = amn

(23)2 = 23×2 = 26

Use our exponent calculator

Exponent Rules and Examples

Negative Exponent Rule

Use the reciprocal of the base and make the exponent sign positive when raising a number to a negative exponent:

a-m = 1/am

2-2 = 1/22 = 1/4

Fractional Exponent

Another method of writing a base raised to a fraction is to take the denominator root of the base and raise it to the numerator power:

am/n = (n√a)m

33/2 = (2√3)3 which is about 5.196

Check your math, since you are aware that 33/2 = 31.5. Remember that brackets are everything, so, note this is not the same as 2√33, which equals 3.

Read about How To Use An Exponential Calculator