# Question: use the general quotpartialquot variables quotsee belowquot on the equation...

###### Question details

Use the general "partial" variables, "see below" on the equation 9 (I have asked this question in another post, I am not sure if someone answered) and show that we can obtain an equation only for the spacial part, with the form : "see below"

question 9:

Translation:

The equation is uni-dimensional wave: "See below"

where U=U(x,t) is the wave equation, show that u(x,t) =
Acos(wt)sin(kx) is a solution of the equation.