Finding Zeros of Rational Functions

Learn how to find zeros of rational functions in this free math video tutorial by Mario's Math Tutoring. We go through 3 examples.

0:16 Example 1 Finding zeros by setting numerator equal to zero
1:40 Example 2 Finding zeros by factoring first to identify any removable discontinuities(holes) in the graph.
2:44 Example 3 Finding Zeros

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[martinmoraleta]

These videos from this channel explain the concepts MUCH better than all the professors I've taken. Thank you very much.

[jessievandivier]

the explanation here is great, i really appreciate the "why" being explained. Why do we find the zeros of the numerator, what does that do? What about the denominator? This answers those questions well when other resources struggle to do so. Thanks!

[johnjoblabrador]

Your explanations are great it shows everything I'm up to this video😁

[jernyvispo-bordaje]

Well explained sir Mario..thank you!
Additional input for my online class this school yr.

[Yuki-pruw]

What if I don't have have a variable in the numerator?

[tonielabutap]

How did the Xsquared - 9 became (x-3)(x+3)?

[vikramkarmarkar]

Mr. Mario, my teacher told me that if a factor was both in the numerator and the denominator, then it was a hole. If a factor is only in the numerator, then it is a zero, and if a factor is only in the denominator, then it is a vertical asymptote. Is that correct?

[jordancarin]

Zeros of f(x)= 1/x-3? Can you please answer it?