SOLUTION: (x/x+y)+(x/x-y)

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Question 23428: (x/x+y)+(x/x-y)
Found 2 solutions by AnlytcPhil, rapaljer:
Answer by AnlytcPhil(1810) About Me  (Show Source):
You can put this solution on YOUR website!
(x/x+y)+(x/x-y)

What you typed means this

 x         x
--- + y + --- - y
 x         x

I'm sure that's not what you meant as that is too easy:

1 + y + 1 - y 

which equals 2.

You didn't put in enough parentheses.  To type an expression all on one line,
you must begin every numerator and every denominator with a "(" and end it with
a "}"; otherwise you cannot tell where it starts and ends.  The only times you
don't need a pair of parentheses around a numerator or denominator is when it
contains only one number or one letter.

What I think you meant was this

  x       x
----- + -----
 x+y     x-y

which you should have typed on one line as:

x/(x+y) + x/(x-y)

==========================================

  x       x
----- + -----
 x+y     x-y

When the denominators have no common factor, as here, you may use
this rule:

     A     C     AD ± CB
    --- ± --- = ---------
     B     D        BD


  x       x      x(x-y) + x(x+y)
----- + ----- = ----------------- = (CAREFUL! NO CANCELLING BETWEEN
 x+y     x-y       (x+y)(x-y)        NUMERATOR AND DENOMINATOR ALLOWED HERE!)


      x² - xy + x² + xy
      -----------------
         (x+y)(x-y)


             2x²
        ------------
         (x+y)(x-y)


Edwin
AnlytcPhil@aol.com

Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
x%2F%28x%2By%29%2Bx%2F%28x-y%29

Because this is an addition problem, it calls for a common denominator, which is (x+y)(x-y).

Now, multiply the first fraction by +%28x-y%29%2F%28x-y%29+ and the second fraction by +%28x%2By%29%2F%28x%2By%29+

It should look like this:
%28x%2F%28x%2By%29%29%2A+%28%28x-y%29%2F%28x-y%29%29 + +%28x%2F%28x-y%29%29%2A%28%28x%2By%29%2F%28x%2By%29%29
%28x%5E2-xy+%2B+x%5E2+%2Bxy%29+%2F+%28%28x%2By%29%2A%28x-y%29%29
%282x%5E2+%29%2F+%28%28x%2By%29%2A%28x-y%29%29

R^2 at SCC