What defines an algebraic fraction

1. Jul 17, 2008

ramstin

O.k. I am trying to figure out what defines an algebraic fraction. I know it has something to do with the denominator but for the life of me I can not make any sense out of my text book examples. Like 3/2x = 0 I guess 3/x*x = 3 divided by no actual number which would be zero but that is the best I can work out after 4 hours of trying to do this section of my homework.

2. Jul 17, 2008

LowlyPion

http://www.themathpage.com/Alg/multiply-algebraic-fractions.htm

3. Jul 17, 2008

HallsofIvy

Staff Emeritus
An algebraic fraction, also caled a rational function, is one polynomial divided by another. The polynomials may be of several variables.

4. Jul 18, 2008

ramstin

O.k. if I have a^2-10a+21/a^2-11a+28 I then get 21/-1a+28 and then 3/-a+4 but my book says I should get a-3/a-4 How did that happen?

5. Jul 18, 2008

LowlyPion

They are asking you to simplify the fraction. Factor the numerator and denominator and simplify.

6. Jul 18, 2008

ramstin

even with simplifying how do you get an a on both sides when their is an odd number of them to begin with?????

7. Jul 18, 2008

LowlyPion

What both sides? You have an expression that is a fraction. You have a numerator and you have a denominator.

After you have factored both equations (top and bottom) you still have an expression that is still an algebraic fraction. When the like terms are canceled top and bottom, you are still left with an algebraic expression - only it's the answer given.