Question

(a+b/a-b）²×（2a-2b／3a+3b）-（a²／a²-b²）÷（a／b）

Answer 1

原式=[(a+b)²/(a-b)²]×[2(a-b)/3(a+b)]-a²/(a+b)(a-b)×b/a
=2(a+b)/3(a-b)-ab/(a+b)(a-b)
=[(2a+2b)(a+b)-3ab]/3(a+b)(a-b)
=(2a²+4ab+2b²-3ab)/(3a²-3b²)
=(2a²+ab+2b²)/(3a²-3b²)

Answer 2

(a+b/a-b)^2*2a-2b/3a+3b -a^2/a^2-b^2÷a/b
=(a+b)^2/(a-b)^2*2(a-b)/[3(a+b)]-a^2/(a+b)(a-b)*b/a
=2(a+b)/3(a-b)-ab/(a+b)(a-b)
=[2(a+b)^2-3ab]/[3(a-b)(a+b)]
=(2a^2+2b^2+ab)/[3(a-b)(a+b)]

Answer 3

2（a^2+b^2+ab）/3(a^2-b^2)