Returns the modified Bessel function, which is equivalent to the Bessel functions evaluated for purely imaginary arguments.
Syntax
BESSELK(x,n)
X is the value at which to evaluate the function.
N is the order of the function. If n is not an integer, it is truncated.
Remarks
 If x is nonnumeric, BESSELK returns the #VALUE! error value.
 If n is nonnumeric, BESSELK returns the #VALUE! error value.
 If n < 0, BESSELK returns the #NUM! error value.
 The nth order modified Bessel function of the variable x is:
where Jn and Yn are the J and Y Bessel functions, respectively.
Example
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How to copy an example
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Selecting an example from Help
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A 
B 
Formula 
Description (Result) 
=BESSELK(1.5, 1) 
Modified Bessel function at 1.5 with an order of 1 (0.277388) 
