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calc/help/atanh
2017-05-21 15:38:25 -07:00

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NAME
atanh - inverse hyperbolic tangent
SYNOPSIS
atanh(x [,eps])
TYPES
x real
eps nonzero real, defaults to epsilon()
return real
DESCRIPTION
Returns the atanh of x to a multiple of eps with error less in
absolute value than .75 * eps.
atanh(x) = ln((1 + x)/(1 - x))/2 is the real number v for whichi
tanh(v) = x.
EXAMPLE
> print atanh(.5,1e-5), atanh(.5,1e-10), atanh(.5,1e-15), atanh(.5,1e-20)
.54931 .5493061443 .549306144334055 .5493061443340548457
LIMITS
unlike sin and cos, x must be real
eps > 0
LIBRARY
NUMBER *qatanh(NUMBER *x, NUMBER *eps)
SEE ALSO
asinh, acosh, asech, acsch, acoth, epsilon