Online calculator simulators?

[Albert Chan]

(07-09-2022 02:15 PM)jonmoore Wrote:  The ArcCos result varied slightly in the final 4 decimal places and the final result after the ArcSin, resulted back at 9. Which is in fact, the correct answer if all of the calculations are done symbolically - three trigonometric functions, followed by their inverses should resolve back to the original number. It looks a little too convenient that Mathematica still resolves to 9 even though all previous calculations are only accurate to 15 significant digits, but it's bang on the nose.

9. really meant 9.00000 (6 sig. diigts)

To get what is actually stored, try Numberform[%]