The value of a number raised to some exponent.
A power is the result of multiplying a number by itself a certain number of times. We use an exponent to show how many times the number is used as a factor.
For example, 2\(^3\) (read as “2 to the power of 3” or “2 cubed”) means 2 × 2 × 2 = 8, where:
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The base is 2
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The exponent is 3
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The power is the result, 8
Why do we need powers?
Using exponents and powers (known as an expression with exponents or exponentiation) are a shorter, and often simpler, way of writing repeated multiplication. Let’s compare:
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Repeated multiplication: 3 × 3 × 3 × 3 × 3
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Expression with an exponent (or power): 3\(^5\)
Which one is shorter? It’s clear: exponentiation!
We often use powers in:
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Scientific notation
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Measurement conversions
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Area and volume formulas
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Understanding large numbers (like a googol or googolplex)
When Do Students Learn About Powers?
Students first encounter powers when they begin to explore exponents and repeated multiplication.
Grades 5–6 – Introduction to Powers and Exponents
Students learn what exponents mean, how to read and write powers, and how to evaluate small powers.
Grades 7+ – Powers in Algebra and Scientific Notation
Students work with negative and zero exponents, apply exponent rules, and use powers in expressions, equations, and scientific notation.
