Why does my child think x⁸ ÷ x² = x⁴?
Your child divides the indices when dividing powers, such as x⁸ ÷ x² = x⁴.
Why children do it
Dividing the powers mirrors multiplying them. Written out, x⁸ ÷ x² is eight x's over two x's, and the two on the bottom cancel two on the top, leaving six. The powers take away, so it's x⁶.
How to help at home
Ask them to write it as a fraction with the x's written out, and cancel them in pairs.
The right way
Simplify: x⁸ ÷ x²
- x⁶Dividing: subtract the indices. 8 minus 2 is 6.
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