The BESSELK () is an engineering function which takes the argument x, n and returns the modified Bessel function. These are equivalent to the Bessel functions evaluated for purely imaginary arguments.
=BESSELK(x,n) In the above syntax, the argument "x" denotes the value at which the function is to be evaluated and "n" denotes the order of the Bessel function. If n is not an integer, it is truncated.
Let us see how the BESSELK function works, with the help of the below video.