Lower bounds for the first zero for nonlinear second order differential equations

摘要

We consider establishing lower bounds for the first zero of the solution of the nonlinear second order initial value problem (p(x)y (x)) + f(x,y(x)) = 0, x 0 y(0)=a 0, y (0)= 0. Using the linear case as a starting point, we prove several of these theorems, comparing them by considering several examples.