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Index notation

We use index notation to show repeated multiplication by the same number.

We can use index notation to simplify the way we write the expression: 2 × 2 × 2 × 2 × 2.

25

This number is read as ‘two to the power of five’.

25 = 2 × 2 × 2 × 2 × 2 = 32

Base

Index or power

Use index notation to show: 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2.

What is the value of the calculation?

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Index notation

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A justifiable conclusion?

Two students in Miss Jones’ class notice an interesting pattern emerging when they are raising negative numbers to different powers.

When we raise a negative number to an odd power, the answer is negative.

When we raise a negative number to an even power the answer is positive.

Using your knowledge of how positive and negative numbers interact when multiplied, can you prove that this is always true?

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Index laws

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Using index laws

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Index laws