Find the eigenvalues and eigenfunctions for the differential operator L(y) = -y'' with boundary conditions y'(0) = 0 and y(5) = 0, which is equivalent to the following BVP
y'' + ̇λ y = 0, y'(0) = 0, y(5) = 0.
(a) Find all eigenvalues λn as function of a positive integer n ≥ 1.
(b) Find the eigenfunctions yn corresponding to the eigenvalues λn found in part (a).