ABSTRACT
A second-order ordinary differential equation solved for the highest derivative has the form y x x ′ ′ = f ( x , y , y x ′ ) . $$ y_{{xx}}^{{''}} = f(x,~y,~y_{x}^{'} ). $$ https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781315117638/585bf32b-5ab3-4664-8be7-28e9abefef4b/content/math3_1.tif"/>
