Hi, I have this problem, but I am stuck in one thing.
Assuming that solutions to are of the form , and that the separation constant is negative, written as with , I need to show that and must satisfy the differential equations
So well, I kind know what to do once I have substituted into ... However, I keep on getting the wrong results:
I get this:
But this is clearly not what should be on both sides :/
I would really appreciate it if any of you could give me a hand. Once I get both results on each side, I will be able to separate the variables.
Thanks a lot!