OO 2. [2 marks] If y = > akack is a power series solution about x = 0 of the ODE k=0 y' + (202 - 2 y =0, then for k sufficiently large, the coefficients ak must satisfy the recurrence relation ak-2 - ak ak-1 - ak-2 (A) akti = (B) ak+1 = - ak- 1 + ak k+1 k+1 (C) akt1 = k+1 (D) ak+1 = - ak-1 - ak (E) None of (A)-(D) k+1