# Measuring an Electron Spin

A electron spin in quantum mechanics is given by the superposition state:

$\large |\Psi\rangle = \frac{i}{2} |\uparrow\rangle + \dfrac{\sqrt{3}}{2} |\downarrow\rangle.$

What is the probability of measuring the spin in the $$z$$-direction to have value equal to $$-\dfrac{\hbar}{2}$$?

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