exo7 2940

Soit \(\omega = \exp\frac {2i\pi}n\). Calculer :

1

\(\sum_{k=0}^{n-1} (1+\omega^k)^n\).

2

\(\sum_{k=0}^{n-1}\sum_{\ell=k}^{n-1} C_\ell^k \omega^{k+\ell}\).