3a/a-4b +a+b/4b-a -7b/a-4b
3a/a-4b +a+b/4b-a -7b/a-4b
(3a-6b)/(a+b) - (5a-6b)/(a-b) - (4a-5b)/(a+b) - (7a-8b)/(a-b
(3a-6b/a+b)-(5a-6b/a-b)-(4a-5b/a+b)-(7a-8b/b-a)
计算:3a+4b/a-b+3b/b-a-4a/a-b
计算:((a+b)(a-b)-(a-b)^2+2b(a-b))/4(a-b)
1.(a-b)^2(b-a)^3(a-b)^-4
a-4b分之3a+4b-a分之a+b-a-4b分之7b=
计算a^2-b^2/a+b-4a(a-b)+b^2/2a-b
a+b>a-b,
(a-b)(a b)
a/b-b/a
因式分解:a×a-4b×b-2a+4b