Let y=y(x), y>0, be a solution curve of the differential equation (1+x^2) d y=y(x-y) d x. If y(0)=1 and y(2 √ 2 )=β, then

Let $\displaystyle y=y(x), y>0$, be a solution curve of the differential equation $\displaystyle \left(1+x^2\right) \mathrm{d} y=y(x-y) \mathrm{d} x$. If $\displaystyle y(0)=1$ and $\displaystyle y(2 \sqrt{2})=\beta$, then