[mycoding]

<img src="http://chart.apis.google.com/chart?cht=tx&amp;chl=(x^2-1)y'+2x=0;y(0)=1"><br>
	<img src="http://chart.apis.google.com/chart?cht=tx&amp;chl=y'=-{2xy^2\over(x^2-1)}"><br>
	<img src="http://chart.apis.google.com/chart?cht=tx&amp;chl=(x^2-1)dy 2xy^2dx=0"><br>
	<img src="http://chart.apis.google.com/chart?cht=tx&amp;chl=y'=-2x(x^2-1)^{-1}y^2 \rightarrow (y'=f(x)g(x))">