已知:a+b=7,ab=12,求(a-b)눀的值

2025-01-19 02:52:48
推荐回答(1个)
回答1:

(a-b)²
=a²-2ab+b²
=a²+2ab+b²-4ab
=(a+b)²-4ab
=7²-4x12
=49-48
=1
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