x^2-1/x^2+x*3x/1-x please help simplify

 x² - 1       3x
-------- · -------
 x² + x     1 - x

All the numerators and denominators
are in descending order except 1 - x
So arrange the 1 - x in descending order,
as -x + 1

 x² - 1       3x
-------- · -------
 x² + x     -x + 1  

Factor the upper left numerator as the
difference of two squares:

 (x - 1)(x + 1)       3x
---------------- · --------
     x² + x         -x + 1

Factor the lower left denominator by
factoring out x

 (x - 1)(x + 1)       3x
---------------- · --------
     x(x + 1)       -x + 1 

Factor the lower right denominator by
factoring out -1, which causes a 
sign change inside the parentheses:

 (x - 1)(x + 1)       3x
---------------- · ----------
     x(x + 1)      -1(x - 1)

Indicate the multiplication of the
numerators and denominators so that
we have just one fraction. Write the
shorter factors first:

     3x(x - 1)(x + 1)      
   -------------------
    -1x(x + 1)(x - 1)

 Cancel the x's
 
      1
     3x(x - 1)(x + 1)      
   -------------------
    -1x(x + 1)(x - 1)
      1

Cancel the (x - 1)'s

      1   1
     3x(x - 1)(x + 1)      
   -------------------
    -1x(x + 1)(x - 1)
      1          1

Cancel the (x + 1)'s

      1   1      1
     3x(x - 1)(x + 1)      
   -------------------
    -1x(x + 1)(x - 1)
      1   1      1

All that's left is

     3
   ----
    -1

which is just

    -3

Edwin