Hello everyone, I have a problem:

I have this signal curve to which I applied a trendline polynomial ^ 3, to fit my curve.
Now I should make a subtraction between the two curves, but do not know how.
I need this because I have to "flatten" the curve of my signal.

On the chart I have included the euquazione trend line, if I understand it should apply the equation to my chart, right?

heOgEQ4.png