化简求值:(a-b+a-b/4ab)*(a+b-a+b/4ab),a=2/3,b=-2/1

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化简求值:(a-b+a-b/4ab)*(a+b-a+b/4ab),a=2/3,b=-2/1

化简求值:(a-b+a-b/4ab)*(a+b-a+b/4ab),a=2/3,b=-2/1
化简求值:(a-b+a-b/4ab)*(a+b-a+b/4ab),a=2/3,b=-2/1

化简求值:(a-b+a-b/4ab)*(a+b-a+b/4ab),a=2/3,b=-2/1
(4ab/a-b+a-b)*(4ab/a+b-a+b),a=2/3,b=-2/1
=16a²b²/2(a-b)×2b
=4a²b/(a-b)
=4×(2/3)²(-2)/(2/3-2)
=32/3

题目明显有误啊

(a-b+a-b/4ab)*(a+b-a+b/4ab)
=(4a^2b-4ab^2+a-b)(4a^2b+4ab^2-a-b)/16a^2b^2
=[a(4ab+1)-b(4ab+1)][a(4ab-1)+b(4ab-1)]/16a^2b^2
=(4ab+1)(a-b)(4ab-1)(a+b)/16a^2b^2
=(16a^2b^2-1)(a^2-b^2)/16a^...

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(a-b+a-b/4ab)*(a+b-a+b/4ab)
=(4a^2b-4ab^2+a-b)(4a^2b+4ab^2-a-b)/16a^2b^2
=[a(4ab+1)-b(4ab+1)][a(4ab-1)+b(4ab-1)]/16a^2b^2
=(4ab+1)(a-b)(4ab-1)(a+b)/16a^2b^2
=(16a^2b^2-1)(a^2-b^2)/16a^2b^2
a=2/3,b=-1/2
a^2b^2=4/9*1/4=1/9
所以:
原式=(16/9-1)(4/9-1/4)/16/9
=7/9(4/9-1/4)/16/9
=7/16(4/9-1/4)
=7/36-7/64
=49/576

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