Ground state energy of harmonic oscillator

[ciscog38]

Homework Statement

2N fermions of mass m are confined by the potential U(x)=1/2(k)(x²) (harmonic oscillator)
What is the ground state energy of the system?

Homework Equations

V(x)=1/2m(ω²)(x²)

The Attempt at a Solution

I know the ground state energy of a simple harmonic oscillator is E= 1/2 ℏω
I'm really quite terrible at this and I am not sure how to proceed with this.

 

[Matterwave]

What does the fact that your particles are fermions have to do with the problem? How do these particles populate the energy states?