先化简再求值:a²b+ab²分之a²-b²÷(2ab分之a²+b²-1),其中a=3+根号5,b=3-根号5.
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先化简再求值:a²b+ab²分之a²-b²÷(2ab分之a²+b²-1),其中a=3+根号5,b=3-根号5.
先化简再求值:a²b+ab²分之a²-b²÷(2ab分之a²+b²-1),其中a=3+根号5,b=3-根号5.
先化简再求值:a²b+ab²分之a²-b²÷(2ab分之a²+b²-1),其中a=3+根号5,b=3-根号5.
原式=(a+b)(a-b)/ab(a+b)÷(a²+b²-2ab)/2ab
=(a-b)/ab×2ab/(a-b)²
=2/(a-b)
=2/(3+√5-3+√5)
=√5/5