The solution of the D.E. \(\sec^2 x \cdot \tan y\,dx + \sec^2 y \cdot \tan x\,dy = 0\) is _____
Q.1 (vii) The solution of the D.E. \(\sec^2 x \cdot \tan y\,dx + \sec^2 y \cdot \tan x\,dy = 0\) is _____
A. \(\tan x \cdot \cot y = c\)
B. \(\cot x - \cot y = c\)
C. \(\tan x \cdot \tan y = c\)
D. \(\cot x - \tan y = c\)