Upper Bound and Lower Bound Finding Zeros Using Synthetic Division

Learn how to use the upper bound and lower bound when doing synthetic division to help you more quickly find the zeros. We go through an example in this free math video tutorial by Mario's Math Tutoring.

0:25 What are Zeros and how to find them.
0:40 Using the Rational Root Theorem to find possible rational Zeros
1:37 Being Strategic when you pick your Zeros to test
2:09 Using the Upper Bound to Narrow Down the Zeros
3:40 Using the Lower Bound to Narrow Down the Zeros
4:40 Quick Summary of the Upper and Lower Bound when doing Synthetic Division

Other Helpful Videos Related to this Topic:

Descartes Rule of Signs

Synthetic Division

Rational Root Theorem

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[Gorgun]

Lord, in class, the distractions are real.

Here, though, I learn in peace and at my own pace! I love it!

[mikesam]

You're a lifesaver, I have a test in three classes and I'd be a dead man without you!

[ThaoNguyen-ybxq]

AMAZINGLY clear and efficient! I love your teach style!

[jeffreyzheng]

Thank you so much mister. I’m having a hard time understanding my teacher but your teachings are way clearer and it helped me understanding the concepts a lot.

[davidrivard]

You're the freakin best dude! My math teacher still doesn't like me and she's the worst, so I'm still not getting very good grades. But I really do appreciate what you're doing.

[Clangdon]

This man is my lord and savior, I have a test on this in 6 minutes

[badgirlrhi]

This video was a total lifesaver! It made the concept 1, 000, 000x easier to understand! thank you!

[David-wthf]

Thank you so much Mario! It always seems that the good math teachers are on YouTube!

[janmaridelapena]

holy scrap i finally found a video that explain how to get them both CLEARLY my life saver THANKS.

[MV-inxs]

Professor Ang OR Professor X your brain exudes greatness.

[daedaluus]

thank you for explaining this clearly!!

[kartikparameshwaran]

I did understand ur point that if we do take negative 6, we will get a lower bound. But what if i accidently take negative 8 and get alternate roots but at negative 6 also this alternate signs are there while performing the synthetic division. Then what to do at that case where you have a chance to miss a point of lower boundedness

[royalfinest]

It doesnt have to be positive number to check for upper bounds (or negative for lower bound). Some domains could sit entirely on the positive side or negative side.

[jenniecamposano]

Can we know the easiest way to find the upper and lower bound?

[elenaisnothere]

what if it’s alternating aand it’s a zero ? do I stop or do I still have to keep going

[ncsyeyy]

Thanks this helps me a lot, of understanding the upper and lower bound😄

[djklsjfjflkdsjfsd]

Thank you! This is a question in my homework but the teacher didn't cover it at all in class. This makes finding terms and zeros a ton easier and guts the big guesswork. Wish my teacher had explained this a week ago. ugh

[adrianpolydorou]

the only glb ulb video that is understandable

[noonesperfect]

Great video, clear explanation, straight to the point .

[christophermolina]

Hey! Does anybody know where I can find the proof of this Theorem?