Complex Numbers And Quadratic Equations question 302

Question: Which one is correct from the following [RPET 2001]

Options:

A) $ \sin (ix)=i\sinh x $

B) $ \cos (ix)=i\cosh x $

C) $ \sin (ix)=-i\sinh x $

D) $ \tan (ix)=-i\tanh x $

Show Answer

Answer:

Correct Answer: A

Solution:

It is obvious.