Solve 
 

1. x cos2 y dx + tan y dy = 0 2. y ln x In y dx + dy = 0 3. sin x sin y dx + cos x cos y dy = 0 4. x = x - 4y dy=x-4y dx 5. (y+1) dx + (4x - y) dy = 0 (Hint: try finding ) 6. (2xy + x+x+) dx = (1 + x) dy = 0 -