3.1 X(eo)=2xnJe-jon where x[n] is a real sequence. Therefore X(e)=Rl∑xnlo/。 ∑xR(-mu)=∑ x[n]cos(on),and xmm)=m∑刈nm∑刈mc-m)=-2 xn] sin(oon) Since cos(on)and sin(on)are, respectively, even and odd functions of o, Xre(eJo) is an even function of o
Why Statistical Mechanics? Understand predict the physical properties of macroscopic systems from the properties of their constituents Deterministic approach ma F need of 6n coordinates at t: r: and v but typically n= moles (1023)! Ensemble?rather than microscopic detail and its surroundings microcanonical, canonical, grand canonical
