Question

prove that cos(ix) = cosh x​

Answer 1

Step-by-step explanation:

know that Cosh(x) = (E^x + E^-x ) / 2 how do i prove that Cosh(x) = Cos(ix) , where i is the imaginary unit similarly Cosh(ix) = Cos(x) and Sin(ix) = i Sinh(x) similarly Sinh(ix) = i Sin(x)

Source https://www.physicsforums.com/threads/how-to-prove-that-cosh-x-cos-ix.597539/

Answer 2

Answer:

10 steps to solve the sum