Algebra 3
2 marks · NormalWrite down an algebraic identity involving squares and simplify it to show it is always true.
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(a + b)^2 = a^2 + 2ab + b^2
Also accept: (a-b)^2 = a^2 - 2ab + b^2
Common mistakes: Omitting the 2ab term; sign errors
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Marking points
B1 · 1 mark · States correct identity, e.g., (a + b)^2 = a^2 + 2ab + b^2
B2 · 1 mark · Shows expansion/simplification correctly (valid for all values)
Worked solution