ok, i'm just starting with this calculator, and still learning a lot (i just acquired the hp 33s). i'm trying to do this:

in DEG mode:

9 sin cos tan atan acos asin = 8.99999986001

in RAD mode:

9 ->RAD sin cos tan atan acos asin ->DEG = 9.00000000009

9 pi x 180 / sin cos tan atan acos asin 180 x pi / = 9.00000000009

does that mean RAD mode is more accurate?

thanks for the comments!