Expectation value for a spin-half particle.

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Homework Statement



Calculate the expectation value of the operator _{}Sz for a spin-half particle known to be in an eigenstate of the operator _{}Sz

Homework Equations






The Attempt at a Solution



I know the eigenvalues for the _{}Sz but how can I find the expectation values from this?
 
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You might start with the definition of expectation value (in equation form)...:wink:
 
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