lesson

Count factors before using the shortcut

1 · Learn

For powers with the same non-zero base, multiplying adds exponents and dividing subtracts them. This follows from counting repeated factors and cancelling equal non-zero factors. Raising a power to a power multiplies the exponents.

These rules do not mean that a² + a³ equals a⁵: addition is a different operation. Keep the base and the operation visible.

a² × a³ = a⁵a⁵ / a² = a³(a²)³ = a⁶
Key words and supplied examples.

2 · Worked example

2³ × 2² = (2×2×2) × (2×2) = 2⁵ = 32. By contrast, 2³ + 2² = 8 + 4 = 12.

3 · Your turn

Simplify x⁴ × x³ and x⁶ / x² for x not equal to zero.

Check your answer

x⁷ and x⁴.

4 · Apply your learning

Expand one example into factors to justify each rule and supply a counterexample to the incorrect addition rule.

Adult guidance and safety

Ask for the reasoning and a check, not only a numerical result. Supply accurate diagrams, coordinate grids and data displays where required. Use varied examples and revisit prerequisite gaps; these short teaching models are not a completed assessment programme.

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Year 8 Maths learning routine

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Which routine will help you learn well in Year 8 Maths?

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