Find the probability of measuring spin up an axis.

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Homework Statement



Set |Ψ> = (1/√ 2) | ↑, z> + (eiθ / √ 2) | ↓, z>.

Find the probability of measuring the spin component of sz to be up the z-axis.
Find the probability of measuring the spin component of sx to be up the x axis.

Homework Equations



I'm not sure.

The Attempt at a Solution



I think I have to find the projection along each axis in the required direction and then multiply by the complex conjugate. How would I go about finding a projection?

Also, I have an equation for <sz>. Is this the same as finding the probability of spin up the z-axis?
 
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