Question:
Mark $(\sqrt{)}$ against the correct answer in the following:
The solution of the $\operatorname{DE} \frac{d y}{d x}=\frac{\left(1+y^{2}\right)}{\left(1+x^{2}\right)}$ is.
A. $(y+x)=\mathrm{C}(1-y x)$
B. $(y-x)=\mathrm{C}(1+y x)$
C. $y=(1+x) C$
D. None of these
Solution:
