Kahlil said that using the equation
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(a + b)2 = a2 + 2ab + b2, , he can find a
similar equation for
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(a − b)2 . Examine his argument. If it is correct, supply any
missing steps or justification; If it is incorrect point out why.
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(a + b)2 = [a + (−b)]2
= a2 + 2a(−b) + (−b)2
= a2 − 2ab + b2
Mathematical Connections 5‐3
2. a.