Grandss wrote:
If someone can explains me how to determine this two coefficient.

Thanks in advance.

Grandss

If you are talking about the L/D coefficient. This is a commonly used
performance metric for gliders. The attached website has an explanation
of how it is calculated for a glider (should be same for powered
aircraft)

http://www.lerc.nasa.gov/WWW/K-12/airplane/glidvec.html