Consider the operators, $\hat{\mathrm{a}}_{+}=\frac{1}{\sqrt{2}}\left(\hat{\mathrm{x}}+\mathrm{i}\hat{\mathrm{p}}_{\mathrm{x}}\right)$ and $\hat{\mathrm{a}}_{-}=\frac{1}{\sqrt{2}}\left(\hat{\mathrm{x}}-\mathrm{i}\hat{\mathrm{p}}_{\mathrm{x}}\right)$, where $\hat{\mathrm{x}}$ and $\hat{\mathrm{p}}_{\mathrm{x}}$ are the position and linear momentum operators, respectively. The commutator, $\left[\hat{\mathrm{a}}_{+}, \hat{\mathrm{a}}_{-}\right]$ is equal to
(a)$\mathrm{i} \hbar$
(b)$-\mathrm{i} \hbar$
(c)$\hbar$
(d)$-\hbar$
Answer
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