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existence of DE solutions

Source: VTRMC 2006 P4

June 2, 2021
differential equationscalculus

Problem Statement

We want to find functions p(t)p(t), q(t)q(t), f(t)f(t) such that
(a) pp and qq are continuous functions on the open interval (0,π)(0,\pi). (b) ff is an infinitely differentiable nonzero function on the whole real line (,)(-\infty,\infty) such that f(0)=f(0)=f(0)f(0)=f'(0)=f''(0). (c) y=sinty=\sin t and y=f(t)y=f(t) are solutions of the differential equation y+p(t)y+q(t)y=0y''+p(t)y'+q(t)y=0 on (0,π)(0,\pi).
Is this possible? Either prove this is not possible, or show this is possible by providing an explicit example of such f,p,qf,p,q.