3a^2 b-6a^2 b-45ab=?

a^2b^2-7ab+10.3a^3b-6a^2b-45ab. ab/a+b=3 a-2ab+b/2a-3ab+2b? -2ab乘以(-a^+6a^b-3a+b) (a-b)^3+2ab(a-b) a^3-ab^2 =a （a^2 -b^2) =a(a+b)(a-b) a+b=4,ab=-2,求代数式（4a-3b-2ab)-(a-6b+ab) 若a+b=3,ab=-2,求(5a-5b-ab)-(4a-6b-3ab) (9a²-6ab+b²)/(3a²-ab),其中b/a=2 已知:a-b=4,ab=3,求多项式(2a+5b-3ab)-(a+6b-ab)-(2ab+2b-2a)的值 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=2 求证a^3+6ab+b^3=(a+b)^3 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 a^2b(a-b)-6ab(b-a), 1/4a^2b^2{3ab(a+b)-5a(ab-b^2)}=? 如果a+b=3,ab=-1,那么(a+b)2-a-b+ab=? ab=-2 a+b=3 求ab(a²+b²)-a-b 1/a+1/b=3则a-ab+b/a+2ab+b值是?