Week 15: Precalculus 11

Adding Rational Expressions with Variable Denominators

This week in math we learned how to add rational expressions with variable denominators.

We will start easy so, if our rational expression was:

Our first step when adding rational expressions is to find a common denominator which would be 6x.

When multiplying the denominator to find a common denominator we only multiply the numerator that goes with it.  So in this case we don’t not need to multiply 12  by 2 because the 12 already has a denominator of 6x. We leave that fraction alone.

Now we have to combine like terms.

Finally if you can simplify we simplify otherwise you have your answer.  Notice we aren’t using equal signs because it is an EXPRESSION and expression’s don’t contain an equal sign.

Lastly we need to define the restriction(s) of our variables; X in this case.

Our restriction would be X cannot equal 0.  Because, fractions cannot contain a 0 as the denominator.

 

 

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