a+b=-2,ab=-3 求a(a05-b05)- - 知识问答

a+b=-2,ab=-3 求a(a05-b05)-a(a+b)05

2个回答

原式=a(a²-b²)-a(a+b)²
=a(a+b)(a-b)-a(a+b)²
=(a+b)[a(a-b)-a(a+b)]
=-2[a(a-b)+2a]
=-2[a²-ab+2a]
=-2(a²+2a+3)
=-2[a(a+2)+3] 【a+2=-b】
=-2[-ab+3]
=-2*6
=-12

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