Why does my child think (x²)³ = x⁵?
Your child adds the indices for a power of a power, such as (x²)³ = x⁵.
Why children do it
Adding powers works for multiplying, so it's tempting here too. But (x²)³ is x² three times: x² × x² × x², which is six x's. A power of a power multiplies the powers, so it's x⁶.
How to help at home
Ask them to write it out: (x²)³ is x² × x² × x², so how many x's is that?
The right way
Simplify: (x²)³
- x² × x² × x²Three lots of x².
- x⁶Add the indices, 2 + 2 + 2, which is the same as 2 × 3.
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