Wave Formula by complex analysis

[zerat2000]

How can I express the general wave formula, y=Acos(wt-kx), by the complex ft and the exponential ft?
Is it right to use Euler's Identity?

 

[Meir Achuz]

You can use Euler if you want, but can just write y=exp(iwt-ikx) .
It's real part is the cos.