Question

a(a+1)-(a*a-b)=-2,ab=5,求(a*a+b*b)/2-2ab的值

Answer 1

a(a+1)-(a*a-b)=a-b=-2

ab=5已知

(a*a+b*b)/2-2ab =[(a-b)²+2ab]/2-2ab=(a-b)²/2-ab=2-5=-3

解决问题

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