已知a+b=5,ab=3求代数式(a²-b²)²的值
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已知a+b=5,ab=3求代数式(a²-b²)²的值
已知a+b=5,ab=3求代数式(a²-b²)²的值
已知a+b=5,ab=3求代数式(a²-b²)²的值
a+b=5
两边平方
a²+2ab+b²=25
a²+b²=25-2ab=19
(a-b)²
=a²-2ab+b²
=19-6
=13
所以原式=(a+b)²(a-b)²
=5²*13
=325
题错了吧,A+B=5 AxB怎么可能得3?