Posts: 49

Threads: 5

Joined: Jan 1970

HP-33S screen (not "show") reads:

sin(3.141592654) radians = -4.102068e-10

3^201 = 7.968420e95

Excel tells me this:

sin(3.141592654) radians = -4.10206856980497E-10

3^201 = 7.96841966627624E+95

Posts: 11

Threads: 5

Joined: Jan 1970

Yes, these are 2 accuracy issues or "problems" that were outlined in the back of the "HP 15C Advanced Functions Handbook"...to get 3^201 correct to 10 digits a calculator must compute to 14 internal digits, and at the time the 15C did it to only 13, so the 10th digit was a 4 instead of the proper 6...if a calc has 15 internal digits it then get the answer of 3^201 to 11 correct digits.

The Sin of 3.141592654 rad is also mentioend in the 15C Advanced Handbook...most cals get only a couple or a few of the correct digits on this one....on HP cals get it right to all 12 digits...(It is interesting to note that the HP 30S that has 24 internal digits only get the Sin of 3.141592654 accurate to 11 digits, wheil the HPs with saturns architecture and apparently the HP33S also, gets it correct to all 12 digits. So comparing that with the 24 internal digits of ther 30S that gets 11 correct i would prsume the HP 48, 49, 33S etc use Pi interrnally to 25 digits to get the Trig functions so accurate.