若ab=2,a+b=3,则（a-b)^2=?

若a/b=2 则a*a-ab+b*b/a*a+b*b等于? 若a-b=3ab,则2a-ab-2b/a+2ab-b=? 若a+b-ab=0,则(3a+3b-ab)/(2a+2b+ab)= 如果a/b=2则a*a-ab+b*b/a*a+b*b求值 1/a+1/b=3则a-ab+b/a+2ab+b值是? 若a/b+b/a=3,求a^2+ab+b^2/a^2-ab+b^2的值 ab/a+b=3 a-2ab+b/2a-3ab+2b? 若a/b=2,求分式a*a+ab-b*b/a*a-2ab+2b*b 若a+b=3,ab=2,则a^2b+ab^2=( ) 若1/a+1/b=3.则a-3ab+b/a+2ab+b的值为多少?、 若ab^2=-6,则-ab(a^2b^5-ab^3-b)=? a^3-ab^2 =a （a^2 -b^2) =a(a+b)(a-b) 若a-b=3,ab=2,则a^2-b^2-6b=? 若ab不等于0,且3a=b,求代数式b/3a-(-b)/a-a/2b/(-b) 若a+b=3 ab=-2,求a+ab+ab+b的值 A-B=-1,AB=-2,则(2A-3B-AB)-(A-2B+3AB)=?” 已知a+b/2ab=3,则3a-7ab+3b/a+3ab+b=? 若a-b=3ab,求2a-ab-2b除以a+2ab-b的值