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Full Version: TRIG and inverse TRIG functions on an HP-17bII
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Hello all:

I just wanted to let you know that I posted a copy of the equations I entered into my 17bII to compute trig. functions in the ARTICLE FORUM. Witness the supreme act of geekdom!

If you have too much patience, they make for piece of mind just in case you are stuck with ONLY your 17bII, and need that trig. answer.

By the way, I really do like the 17bII a lot, I just wish that they would have included either RPL or keystroke programming. This trig. exercise was made MUCH harder since I couldn't implement CORDIC algorithms to calculate these functions! But, it was a challenge...

Thanks,
Bruce.

p.s. I finally decided that the HP-42s was the answer to all my calculator wishes. I just got one, and I am now fulfilled!

The short way to SIN and COS:

(SIGMA means the summation symbol on HP-17BII)

SINX=SIGMA(N:0:13:1:(-1)^N*X^(2*N+1)/FACT(2*N+1))

and

COSX=SIGMA(N:0:13:1:(-1)^N*X^(2*N)/FACT(2*N))

(X is the angle in rad between 0 and Pi/2)

Other formulas (inverse and hyperbolic) later,
if you are interested.