Question

.-. almost an hour an noones helped me.... fun

Answer 1

i need help coming up with examples of polynomials that you would have to use Descartes' rule and the fundamental theorem of algebra in order to solve it. it dosent even have to be examples it can be an equation or anything

Answer 2

if thats what youre talking about http://www.purplemath.com/modules/drofsign.htm

Answer 3

nooo ive looked at that and it doesnt help. i want something that doesnt have 6 different degrees in 1 problem

Answer 4

Rejecting the help that Positron offered you was a bit hasty. Descartes' Rule applies to polynomials of any degree. Too bad that the first example in that web page involved a fifth order poly. Doing another Internet search for Descartes' Rule would probably turn up examples that are shorter and simpler.

Try inventing a simple trinomial (2nd order equation): x^2 -2x-3. How many sign changes do you see? I see just one: from +x^2 to -2x. Thus, ONE is the maximum number of positive zeros this poly would have. Simple as that.

Answer 5

i already did look thorough google, and came up with nothing but 5th and 6th degree ones. and i went through the page he suggested and that was all that was on there too.

Answer 6

Look at x^2 -2x-3=0 and actually find the zeros. This factors into (x-3)(x+1)=0. So the zeros / roots are 3 and -1. How many positive zeros? ONE. Just as we predicted.

You can invent any poly you want. Use a combo of + and - signs. Then count the number of sign changes (pos to neg or neg to pos). That number is the max number of positive roots your poly will have.

Answer 7

Please note that I had to look up "Descartes' Rule" myself as a refresher, and that I chose to skim through the page shared with you by the other helper. My opinion is that it'd be worth your time to read that page, now that I've given you a simpler example, and obtain a deeper understanding of applications of Descartes' Rule that way. Doing so will take you a lot less time than the hour you've been waiting for help here on OpenStudy.

I know you're also expected to find, understand and apply the Fundamental Theorem of Algebra, but I've made other plans for the afternoon and need to get off the Internet. If you wish, re-post this question with a header like this :"Help with Fundamental Theorem of Algebra." But I'm hoping you'll actually read what you can find on the Internet (even if what you find doesn't match what you'd hoped for 100%). Good luck.

Answer 8

thank you c: good bye