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For the spin 1/2 state |Sx: >evaluate both sides of the inequality (1.146), that is
〈(ΔA)²〉〈(ΔB)²〉≥ 1/4|〈[A, B]〉|²
for the operators A = Sₓ, and B = Sᵧ, and show that the inequality is satisfied. Repeat for the operators A = S and B = Sᵧ