grandes-ecoles 2013 QII.C.1

grandes-ecoles · France · centrale-maths1__psi Sequences and Series Functional Equations and Identities via Series
Using Euler's formula, justify that for $( n , k )$ in $\mathbb { N } \times \mathbb { N }$,
$$I _ { n , k } = \sum _ { m = 0 } ^ { k } \frac { A _ { m , k } } { 2 \pi } \int _ { - \pi } ^ { \pi } e ^ { i t ( 2 m - k - n ) } \mathrm { d } t$$
with $A _ { m , k }$ constants to be determined.
Using Euler's formula, justify that for $( n , k )$ in $\mathbb { N } \times \mathbb { N }$,

$$I _ { n , k } = \sum _ { m = 0 } ^ { k } \frac { A _ { m , k } } { 2 \pi } \int _ { - \pi } ^ { \pi } e ^ { i t ( 2 m - k - n ) } \mathrm { d } t$$

with $A _ { m , k }$ constants to be determined.