polynomial trendline

[Nathoucan]

How can I calculate from two series of values (x and y) entered in an Excel
table the polynomial trendline equation.This without putting it into a graph.
I want to use the equation to calculate specific points after.

 

[Jerry W. Lewis]

You can calculate the polynomial coefficients with LINEST
http://people.stfx.ca/bliengme/ExcelTips/Polynomial.htm
Similarly, you can predict unknown values without the intermediate step of
obtaining the coefficients with TREND function.

Jerry