计算或化简 (1)12xy/5a÷8x^2y (2)1- x-y/x+2y÷x^2-y^2/x^2+4xy+4y^2
计算或化简 (1)12xy/5a÷8x^2y (2)1- x-y/x+2y÷x^2-y^2/x^2+4xy+4y^2
计算或化简
(1)12xy/5a÷8x^2y (2)1- x-y/x+2y÷x^2-y^2/x^2+4xy+4y^2
(3)(-ax^4y^3)÷(5/6ax^2y^2)=
(4)(-2a^3b^2)^3÷(-3ab^3)^2=
(5)3a/5xy=( )/10axy (a≠0)
(6)a+2/a^2-4=1/( )