I have a series of x and y values for which I am trying to find quadratic coefficients for the equation.

I can get these values off the trendline if I plot a graph, however I want to get them via an equation so I can use them in other equations. This way the input information can be changed and still give equation coefficients without having to take them off a graph.

How do I do this? I can't find any function on excel what will do it. If it can't does anyone know a method I can use to calculate these?

Regards

Ian