(0.5a^2+ab+0.5b^2)÷（a+b)=_____

若a-b=1,ab=-2,则(a+1)(b-1)=_____. a(a-1)-(a×a-b)=-5,求(a×a+b×b)÷2-ab 先化简,再求值;[(2a-b/a b)-(b/a-b)]÷{(a-2b/a b) [ab/(a-b)2]},其中b/a= 若a/b=2 则a*a-ab+b*b/a*a+b*b等于? 计算(b)/(a-b)-(b^3)/(a^3-2a^2b+ab^2)÷(ab+b^2)/(a^2-b^2)的值,其中a= a+b/2ab 2AB/A+B 化简 (a²+b²/a²-b²-a-b/a+b)÷2ab/(a-b)(a+b)& 已知a+2b=0,求a*a+2ab-b*b/2a*a+ab+b*b 若a/b=2,求分式a*a+ab-b*b/a*a-2ab+2b*b 单项式3a^2b、2ab、-3ab^2、-4a^2b、3ab的和为_____. ①已知a^2+b^2-4a-2b+5=0,则[根号(ab^3)+根号(a^3b)-ab]÷根号(ab)的值为_____