1. (X2+2y)dy=(cosx-2xy)dx
x2y+y2=sinx+C
2. (2y+x)dy=(3x2-y)dx
y2+xy=x3+C
3. (2x2+4y2)dx+8xydy=0
2/3x2+4xy2+C=0
4. (2xy+1)dy=(3x2-y2)dx
xy2+y=x2+1
5. (ey+x-3y2)dy=(2x-y)dx
ey+xy=x2+y3
6. (6x2+y)dx+(9y2-2yx)dy=0
2x3+3y3-y2+2xy+C=0
7. (8x2y+7)dx+(2x-4y+3)dy=0
4x2-2y2+4xy+7x+3y+C=0
15. (3x+6y+4)dx+(2x-5y+7)dy=0
-y2+4xy+4x+7y+C=0
16. y3dx+(2xy2+3y)dy=0
y2+2y-2xy+C=0
17. dy/dx=(2x-y)/(2y+x-3y2)
y2+xy=x2+y3