若a+3b=0,则(1-b/a+2b)÷a^2+2ab+b^2/a^2-4b^2

若a+3b=0,则(1-b/a+2b)÷a^2+2ab+b^2/a^2-4b^2
若a+3b=0,则(1-b/a+2b)÷a^2+2ab+b^2/a^2-4b^2

若a+3b=0,则(1-b/a+2b)÷a^2+2ab+b^2/a^2-4b^2
将a=-3b代入所求式中去,进行化简.(1+7b/3)÷9b-6b^2+1/9-4b^2=(3+7b)/27b-10b^2+1/9