User:Ghm

我的网页，来自中国
我来学习，还不懂啊， 练习一下 Problem 5

Problem Statement
Consider:

$$ \ xyy^{''} + x(y^{'})^{2} + yy^{'} = 0 $$ Given that the 1st exactness condition is satisfied show that the 2nd exactness condition is satisfied

$$\ F(x,y,y^{'})=xyy^{'} \qquad $$ $$\qquad F^{'}=\ xyy^{''} + x(y^{'})^{2} + yy^{'} = 0$$

$$(xyy^{'})^{'}=0$$

$$xyy^{'}=c     \quad      yy^{'}=c/x$$ $$\ frac{y^{2}}{2} = $$