Question for Trig Gurus

[toml_12953]

(12-01-2014 10:54 PM)Namir Wrote:  [quote='PANAMATIK' pid='22183' dateline='1417466789']

The Casio fx-10 from 1974 does not seem to have Arc functions built in, at least has no keys for it.

Bernhard

The manual I found was for both the FX-10 and FX-50. It doesn't say there's a difference between the keyboards so I figured both had all the functions. Here's a BASIC subroutine to calculate ATN(X):

30000 REM ARCTANGENT: A9=ATN(X9)
30300 REM VARIABLES USED: A9,B9,C9,T9,X9
30310 T9=SGN(X9): X9=ABS(X9): C9=0 : IF X9>1 THEN C9=1 : X9=1/X9
30330 A9=X9*X9 : B9=((2.86623E-3*A9-1.61657E-2)*A9+4.29096E-2)*A9
30330 B9=((((B9-7.5289E-2)* A9+.106563)* A9-.142089)*A9+.199936)*A9
30340 A9=((B9-.333332)*A9+1)*X9 : IF C9=1 THEN A9=1.5708-A9
30350 A9=T9*A9 : RETURN