Question

( a + b + c )²

( a + b - c )²

( a- b - c)²

Answer 1

(a + b + c)² = a² + b² + c² + 2ab + 2bc + 2ac

(a + b - c)² = a² + b² + c² + 2ab - 2bc - 2ac

(a - b - c)² = a² + b² + c² - 2ab + 2bc - 2ac

Answer 2

\(\left(a+b+c\right)^2=a^2+b^2+c^2+2ab+2bc+2ac.\)

\(\left(a+b-c\right)^2=a^2+b^2+c^2+2ab-2bc-2ac.\)

\(\left(a-b-c\right)^2=a^2+b^2+c^2-2ab+2bc-2ac.\)

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