Question

求化简 (a-b)/(a+2b)除以(a^2-b^2)/(a^2+4ab+b^2)-(3a^2-4ab)/(a^2+ab

Answer 1

(a-b)/(a+2b)除以(a^2-b^2)/(a^2+4ab+4b^2)-(3a^2-4ab)/(a^2+ab)

=(a-b)/(a+2b)÷ (a+b)(a-b)/(a+2b)^2-a(3a-4b)/a(a+b)

=(a+2b)/(a+b)-(3a-4b)/(a+b)

=(a+2b-3a+4b)/(a+b)

=(6b-2a)/(a+b)

=2(3b-a)/(a+b)