-a^3b+2a^2b-ab

(a-b)^3+2ab(a-b) a+b/2ab 2AB/A+B a+b/2ab (a-b)(3ab+2a²b-b³) ab/a+b=3 a-2ab+b/2a-3ab+2b? ab^3+b^2+b-a+1 -2ab乘以(-a^+6a^b-3a+b) 18ab(a-b)^2-12a(b-a)^3 (ab(a^-2ab)-a^2b(a-3b))÷（3a^b） a^3-ab^2 =a （a^2 -b^2) =a(a+b)(a-b) 3(-ab+2a)-(3a-b) 3(-ab+2a)-(3a-b) (a-b)平方-2ab(b-a) 已知3a*a+ab-2b*b=0(a不等于0,b不等于0),求a/b-b/a-(a*a+b*b)/ab的值. (a-b)(a^5+a^4b+a^3b^2+ab^4+b^5)bggg b/a+a/b=3,求2ab/(a*a+b*b)-(3a*a+ab+3b*b)/2ab的值 已知a*a-ab=3,ab+b*b=-5,求代数式a*a+b*b与a*a-2ab-b*b的值