Differential Equations

1

Formation of a Differential Equation

1.1 INTRODUCTION

The general laws of science, engineering, medicine, social sciences, population dynamics and the like where the rate of change of quantities is involved are usually modelled as differential equations. Formation of differential equations, solution and interpretation of the results are of practical interest, especially for engineers and physicists, as they deal with many engineering and physical problems. So, we study in this chapter, methods of solution of ordinary differential equations of the first order and first degree, their applications to Newton's law of cooling the law of natural growth and decay, and orthogonal trajectories.

Further, methods of solution of linear differential equations ...