1)a2- b2 / 6a2b2 : a+b/3ab 2)a2b-4b3/3ab2 × a2b/a2-2ab 3)x2-xy/x2+xy × x2y + xy2/xy

1) a2-b2/6a2b2 : a+b/3ab = (a-b)(a+b)/3ab*2ab * 3ab/a+b= a-b/2ab
2) a2b-4b3/3ab2*a2b/a2-2ab = b(a2-4b)/3ab2 * a2b/a(a-2b)= (a-2b)(a+2b)/3a(a-2b)=
a+2b/3a
3) x2-xy/x2+xy × x2y + xy2/xy = x(x-y)/x(x+y) * y= y(x-y)/x+y