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If (a+b)^2=10, if ab=-2 calculate a^2+b^2



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5 votes

Answer:

(a +b)² = a² + b² +2ab

10 = a² + b² + 2(-2). [ ab = -2]

10 = a² + b² - 4

a² +b² = 10 +4

a² +b² =14

hope it helps