Bug: HP Prime can't do Log's

[Dieter]

(12-14-2015 06:35 AM)cyrille de brébisson Wrote:  Prime does give the correct answer to LN(81) and to LN(3) (within the calculator 12 digit accuracy). And dividing these 2 answers by each others do indeed yield 3.99...99).

Please forgive my ignorance, and maybe I get something wrong here, but: if there is a built-in function log(a, b) I would expect it to be evaluated with the usual 15 digit internal precision. Else there is no benefit compared to a manually calculated ln(a)/ln/b). ;-)

Another example: take for instance the 35s and its function for the xth root of y. Manually calculating the cube root of 125 via 3 [1/x] [y^x] returns 4,99999999999. Using the dedicated XROOT function (125 [ENTER] 3 XROOT) yields the exact result 5. Simply because of the extended 15-digit internal precision. That's what I would have expected here as well for the log(a, b) function.

Dieter