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edmar
Sep 6, 2007, 10:32 PM
This is a Rational Expression

Add: 2/x+1 + 1/x-1

Capuchin
Sep 6, 2007, 11:40 PM
\frac{2}{x+1}+\frac{1}{x-1}

You need to get the denominators the same, you can do this by multiplying either term by 1 (anything with the same numerator and denominator):

\frac{2(x-1)}{(x+1)(x-1)}+\frac{1(x+1)}{(x+1)(x-1)}

Can you take it from here?

s_cianci
Sep 8, 2007, 10:34 AM
You need a common denominator. Determine the LCD for x + 1 and x - 1. Multiply each of the original numerators by the missing factor in the original denominator. Then combine the terms in the numerator.