Testing a square identity
Testing a square identity
Secondary 2
3 marks
TGM Original Questions
A learner claims \((a-b)^2=a^2-b^2\). Explain the error using expansion, and give a numerical counterexample.[3]
Solution:
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Answer:Correct expansion: \(a^2-2ab+b^2\); for example \(a=5,b=2\) gives 9 and 21.
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