In the formula for determining acoustic surface impedance: Z = -j.Zc.cotg(kd). Does the symbol "cotg" represent the cotagent hyperbolic function?

Hi, This formula that I taken from the book "Propagation of Sound in Porous Media" of Jean F. Allard and the book does not have a specific explanation for this symbol in it. I'm wondering whether...

28 March 2024 6,553 2 View