Hi everyone! Having spent many fruitless hours Googling this I stumbled upon this forum, and am hoping you may be able to help... I'm looking for a way to interpolate between two polynomials. These two lines are related and run along in a near-parallel fashion, and I want to divide the gap between them into 5 equal parts. I can do it by creating a table of values, but really I want to be able to create an equation directly. Simply dividing up the difference between the coefficients produces something which looks close to what I want (it's a similar shape and lies between the original two lines), but is clearly wrong. Am I making sense?!? Does anyone have any ideas, or do I need to provide more detail? Am I even in the right forum??? Cheers, Joe.