**Public Function ASec( _
ByVal vX As Variant _
) As Variant**

**"Inverse Secant" or "Arcsecant" **

Angle whose secant is X.

Inverse of the Secant function.

**Examples:** ASec(-0.5) = "3.1415926535898|-1.31695789692482"
IsNull(ASec(0)) = True
ASec(0.5) = "-3.5527136788005E-15|1.31695789692482"
ASec(1) = -3.5527136788005E-15
ASec(1.5) = 0.84106867056793
ASec(2) = 1.0471975511966
ASec(3) = 1.23095941734077
ASec(10) = 1.47062890563334
ASec("2.3|-4.5") = "1.4820015760061|-0.175981348644681"

**See also:** Secant Function
ASin Function
ACot Function
ACsc Function
ASecH Function
Arcsec Function

**vX:** Function returns the principal value of the angle whose secant (expressed in radians) is vX. Function returns Null if vX is Null or cannot be fixed up to a real or complex number (as defined by the ComplexStringToReals function). Complex numbers are represented within strings as "R|I" where R is the real part and I is the imaginary part.

**Note:** Microsoft named this function Arcsec within their Derived Math Function help topic. Copyright 1996-1999 Entisoft

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