Radio Shack TRS-80 Model 3 - Page 249

APPENDIX
E / DerivedFunctions
Function
SECANT
COSECANT
COTANGENT
INVERSE SINE
INVERSE COSINE
INVERSE SECANT
INVERSE COSECANT
INVERSE COTANGENT
HYPERBOLIC SINE
HYPOBOLIC
COSINE
HYPERBOLIC TANGENT
HYPERBOLIC SECANT
HYPERBOLIC COSECANT
HYPERBOLIC COTANGENT
INVERSE HYPERBOLIC
SINE
INVERSE HYPERBOLIC
COSINE
INVERSE HYPERBOLIC
TANGENT
INVERSE HYPERBOLIC
SECANT
INVERSE HYPERBOLIC
COSECANT
INVERSE HYPERBOLIC
COTANGENT
Inverse Sine
Inverse Cosine
Inverse Secant
Inverse Cosecant
Inverse Hyper. Cosine
Inverse Hyper. Tangent
Inverse Hyper. Secant
Inverse Hyper. Cosecant
Inverse Hyper. Cotangent
Function Expressed in Terms of Model III BASIC Functions.
X
is in radians.
SEC(X) 1/COS(X)
CSC(X)
= 1/SIN(X)
COT(X) 1/TAN(X)
ARCSIN(X)
= ATN(X/SQR( - X*X +1»
ARCCOS(X)
- ATN(X/SQR( X*X + 1» +1.5708
ARCSEC(X)
= ATN(SQR(X*X -1» + (SGN(X) -1 )*1.5708
ARCCSC(X) ATN(1/SQR(X*X
- 1) + (SGN(X) - 1)*1.5708
ARCCOT(X)
= ATN(X) + 1.5708
SINH(X)
= (EXP(X) - EXP( - X»/2
COSH(X) (EXP(X) + EXP( X»/2
TANH(X)
= EXP( - X)/(EXP(X) + EXP( - X))*2 + 1
SECH(X) 2/(EXP(X) + EXP(
X)
CSCH(X) = 2/(EXP(X) EXP( - X»
COTH(X) = EXP( - X)/(EXP(X) - EXP( - X))*2 +1
ARGSINH(X) LOG(X + SQR(X*X + 1)
ARGCOSH(X) = LOG(X + SQR(X*X - 1»
ARGTANH(X) = LOG((1 + X)/(1 X))/2
ARGSECH(X)
= LOG((SQR( - X*X + 1) +1 )/X)
ARGCSCH(X)
= LOG((SGN(X)*SQR(X*X + 1) + 1)/X)
ARGCOTH(X)
= LOG((X + 1)/(X -1 )/2
Valid Input Ranges
-1<X<1
-1<X<1
X < - or X>1
X
< -1 or X > 1
X>1
X*X < 1
0<X<1
X <> 0
X*X> 1
Certain special values are mathematically undefined, but our functions may
provide invalid values:
TAN and SEC of 90 and 270 degrees
COT and CSC of 0 and 180 degrees
For example, TAN( 1.5708) returns a value but TAN(90* .01745329) returns a DIVISION
BY ZERO
error. 90* .01745329 = 1.5708
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