Finding all the Zeros of a Polynomial - Example 3

Finding all the Zeros of a Polynomial - Example 3. In this video, I use the rational roots test to find all possible rational roots; after finding one I use long division to factor, and then repeat! Very fun!

Category:

Education

Tags:

• math
• algebra
• zero
• root
• solution
• find
• finding
• austin
• polynomial
• remainder
• theorem
• factor
• long
• synthetic
• division

[rabbifilms]

@patrickJMT Can't one just plug the function into a calculator, see where the lines intersect, and find the zeros that way? or anyowne..

[patrickJMT]

@rabbifilms well, if you are going to use a calculator, just use it to find the solutions. why even bother to graph.

[jeleemay97]

is there a way to tell all the zeros without plugging and chugging every possible rational zero? because on tests and quizzes, that is very time consuming :(

[patrickJMT]

@jeleemay97 yes, it is very time consuming. to find zeros of a polynomial is actually a deep and important concept.

[coolman6566]

I have x^4 + 6x^2 + 9. I need to find all zeroes. all the zeros i found were plus minus 1, 3, and 9. i tried all 6 of them and plugged them in, but none of them came out to equal zero

[patrickJMT]

@coolman6566 there are no zeros for that

[Crossfeet606441]

The next time my math teacher says "......blah....blah......blah" and stuffs like that for 40 - 60 mins, my bedroom will become my classroom, and the book will be my laptop, the page of the lesson will be youtube, and you will be my teacher for just 10 - 20 mins.

[patrickJMT]

@richardsun7 ha : ) if it is a diff eq exam, i think you are watching the wrong videos!

[x0Gamble0x]

can u help me with my homework? please

[mjohnsoncuber]

YEAAAAAAAAAHHHH I FEEL LIKKA BAWSS

[AhiskaRustem13]

10x a lot, this was sooo helpful

[engysamad1]

Excellent .Thanks a lot . You are master in math :)

[hangv001]

can you please come teach at my school? I begggggg you!!!!!! My teacher doesn't know how to teach. She spent 30 minutes just to explain how to find rational zero. Thank you so much!

[timothytcliu]

everything else has online sources, but hey what about math? this is brilliant. thanks!

[AliensHateUs]

@jeleeymay97 You could use Descartes Law of Signs to figure out how many zeros you will have, however DLS does not show you which specific possible factors are zeros, just how many zeros there could be.