The third one should be your answer
Step-by-step explanation:
The coefficent of the x variable is b.
The formula for the period is

Here, b is 6 so we have

So the period is pi/3, or 60 degrees
I think this is how you do it.
Answer:
25 percent
Step-by-step explanation:
![\dfrac\partial{\partial y}\left[e^{2y}-y\cos xy\right]=2e^{2y}-\cos xy+xy\sin xy](https://tex.z-dn.net/?f=%5Cdfrac%5Cpartial%7B%5Cpartial%20y%7D%5Cleft%5Be%5E%7B2y%7D-y%5Ccos%20xy%5Cright%5D%3D2e%5E%7B2y%7D-%5Ccos%20xy%2Bxy%5Csin%20xy)
![\dfrac\partial{\partial x}\left[2xe^{2y}-y\cos xy+2y\right]=2e^{2y}+y\sin xy](https://tex.z-dn.net/?f=%5Cdfrac%5Cpartial%7B%5Cpartial%20x%7D%5Cleft%5B2xe%5E%7B2y%7D-y%5Ccos%20xy%2B2y%5Cright%5D%3D2e%5E%7B2y%7D%2By%5Csin%20xy)
The partial derivatives are not equal, so the equation is not exact.