How do I enter a quadratic and cubit-fit equations?

[DianeD]

I have a data set the I want to evaluate using quadratic and cubit fits- can
someone provide the proper equations? Adn what about plotting the funtions?

 

[Bernard Liengme]

1) read Help to learn about Trendlines - make an XY chart first
2) visit my site to learn about LINEST to find polynomial coefficients
http://www.stfx.ca/people/bliengme/ExcelTips/Polynomial.htm
3) to lean about charting - buy a book or visit
http://peltiertech.com/Excel/ChartsHowTo/index.html
best wishes