x/x-1+1/1-x

Question

Just need answer and explanation why?

Answer 1

i presume this is

y = x/(x-1) + 1/(1-x)

 

Multiply last term by -1/-1 in order to give the expressions a common denominator.

 

y = x/(x-1) - 1/(x-1)    

 

Combine the expressions, since they now have a common denominator

 

y = (x-1)/(x-1)

 

y = 1  except that the function is undefined when x = 1,  because that would mean you were dividing by zero.