Question

$a {}^{2} + b {}^{2} + 2ab + 2bc + 2ac$
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Answer 1

Answer:

a² + b² + 2(ab+bc+ca)

= a²+b²+c² +2(ab+bc+ca) - c²

= (a+b+c)² - c²

= (a+b+c+c)(a+b+c-c)

= (a+b+2c)(a+b)