Differential Equation: $ye^{xy} dx + xe^{xy} dy = 0$

Please help me to solve this differential equation

yexydx+xexydy=0

$ye^{xy}\,dx + xe^{xy}\,dy = 0$

$e^{xy}(y\,dx + x\,dy) = 0$

$e^{xy} \, d(xy) = 0$

$\displaystyle \int e^{xy} \, d(xy) = 0$

$e^{xy} = c$           answer

Boss pahelp naman po....pleassssssss sir.....
1. (2ycosx + sin⁴x)dx = sin x dy when x=½π, y=1

2. (1+4xy-4x²y) dx +(x²-x³)dy =0 when x=2, y=¼