How to Calculate Uncertainty for Spin-1/2 Eigenstates?

nmsurobert
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Homework Statement


Calculate ΔSx and ΔSy for an eigenstate S^z for a spin-1/2 particle. Check to see if the uncertainty relation ΔSxΔSy ≥ ħ|<Sz>|/2 is satisfied.

Homework Equations

The Attempt at a Solution


I'm confused on where to start. As I am with most of this quantum stuff.
From what we've done earlier in the class...
ΔS = √(<S2> - <S>2)

and i believe that <Sx2> = ħ2/4 = <Sy2> = <Sz2>

but i don't know where I'm supposed to go from there.
 
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You need to work out <S> now.
Review what is meant by "spin half".
 
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