2/(1-m)-1/(m-1)=2/(1-m)+1/(1-m)=3/(1-m)2x/(x-y )-y/(y-x) -(y-2x)/(x-y)2x/(x-y)+y/(x-y)-(y-2x)/(x-y)=(2x+y-y+2x)/(x-y)=4x/(x-y)12/(m²-9 )-2/(m-3)=12/(m-3)(m+3)-2/(m-3)=12/(m-3)(m+3)-2(m+3)/(m-3)(m...