[" 391.The solution of the differential equation "(dy)/(dx)=(x-y)^(2)],[" when "y(1)=1," is "],[[" (1) "log_(e)|(2-y)/(2-x)|=2(y-1),],[" (2) "log_(e)|(2-x)/(2-y)|=x+y,],[" (3) "-log_(e)|(1+x-y)/(1-x+y)|,=x+y-2],[" (4) "-log_(e)|(1-x+y)/(1+x-y)|,=2(x-1)]]