On the Zeros of First-Order Differential Equations

The zeros of solutions of equations were widely studied for the second-order ordinary differential equations in the frame of Sturm–Liouville theory, particularly for Schrödinger and Emden–Fowler equations. However, surprisingly they weren’t studied for the first order equations. In this paper, we study the zeros of solutions of a basic class of first-order equations making use of a brand-new method coming from a recent principle related to real functions.