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B2. Laws of indices
Multiplication

When a number raised to a power is multiplied by that same number raised to another power, the result can be written simply as a single power of that number. 23 × 22 = 2×2×2 × 2×2 = 25 Similarly, 54 × 53 = 5×5×5×5 × 5×5×5 = 57

There is a rule here for how the indices are combined. This rule is often called The First Law of Indices. am × an = am+n Clearly by the above rule: ( 54)3 = 54 × 54 × 54 = 512, which suggests another rule (The Third Law of Indices): (am)n = amn Practise using the first law of indices to simplify an expression. Press "Simplify" to get started:

× Simplifies to:

Coded:

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