grandes-ecoles 2018 Q33

grandes-ecoles · France · centrale-maths2__official Taylor series Prove smoothness or power series expandability of a function

Show an analogous result to $f(0) = \frac{1}{2\pi} \int_0^{2\pi} f(r\cos(t), r\sin(t))\, \mathrm{d}t$ for harmonic functions.

Show an analogous result to $f(0) = \frac{1}{2\pi} \int_0^{2\pi} f(r\cos(t), r\sin(t))\, \mathrm{d}t$ for harmonic functions.