Calculating area graphically on the HP50g appears inaccurate

[Han]

I see what you mean now. Yes, your original suspicion is correct. The AREA function in the graph view uses the actual x-values where the cursor is located. Thus, when you find the root, the cursor is moved to the pixel closest to the actual root. In this case, using the default settings, the cursor is placed at x=3.1 while the ROOT function returns a more precise result. The AREA function is simply giving the area between x=0 and x=3.1.