Question

计算：a2-2ab/-ab+b2÷(a2/a-b÷2ab/2b-a)

Answer 1

(a^2-2ab)/(-ab+b^2)÷a^2/(a-b)÷2ab/(2b-a)

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

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

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

=a(a-2b)/b*1/a^2*(a-2b)/2ab

=(a-2b)/b*1/a^2*(a-2b)/2b

=(a-2b)^2/(2a^2b^2)