Bug: HP Prime can't do Log's

[carey]

I think the simple question is why a problem that a high school student can solve exactly, e.g., log (base 3) of 81 = 4 does not return exactly 4 on the Prime, but does return 4 on most current calculators (and computational software).

Thank you for your explanation about “guard digits” — it was very helpful, but disagree that in this case it would “hide the error from the user.” As cyrille correctly pointed out in this case “more precision returns a less accurate result, and less precision will return a more accurate result.”

Not trying to kick the prime, just trying to get a straight answer. I'm satisfied with the guard digit explanation but disagree that not using them is an advantage in this case.