(a+b)( )=-a^2-2ab-b^2

a/b=2 ,(a*a-ab+b*b)/(a*a+b*b)= 若a/b=2 则a*a-ab+b*b/a*a+b*b等于? 如果a/b=2则a*a-ab+b*b/a*a+b*b求值 a+b/2ab 2AB/A+B a+b/2ab ab/a+b=3 a-2ab+b/2a-3ab+2b? 4ab/b^2(a-b)= 若a/b=2,求分式a*a+ab-b*b/a*a-2ab+2b*b 已知a+2b=0,求a*a+2ab-b*b/2a*a+ab+b*b （a+ab)-[(ab-2b)-a]-(-9ab),其中a+b=-7,ab=3. a^3-ab^2 =a （a^2 -b^2) =a(a+b)(a-b) a(a+b)(a-b)-a(a+b)(a+b),其中(a+b)=1,ab=-1/2 a(a-1)-(a×a-b)=-5,求(a×a+b×b)÷2-ab (a-b)平方-2ab(b-a) (a-b)^3+2ab(a-b) 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. b/a-b +a/a+b +2ab/a^2-b^2=