先化简再求值1.当a=1+√2,b=1-√2时,求(1÷a-b-1÷a+b)÷b÷a²-2ab+b²的值_数学解答

先化简再求值1.当a=1+√2,b=1-√2时,求(1÷a-b-1÷a+b)÷b÷a²-2ab+b²的值

人气：129 ℃　时间：2020-03-30 02:36:38

解答

(1÷a-b-1÷a+b)÷b÷a²-2ab+b²
=(2b/[(a-b)(a+b)]÷[b÷(a-b)²]
=2b(a-b)²/[b(a-b)(a+b)]
=2(a-b)/(a+b)
=4√2/2
=2√2