Is Braket Operation Legal? Elaborate Here

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Is this operation legal?

\langle A_1|BA|A_2\rangle=A_2\langle A_1|B|A_2\rangle

If so, please elaborate on that.

Thanks.
 
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If |A_2 \rangle is an eigenvector of the operator \mathbf{A} with eigenvalue A_2 then your operations are correct.
 
So

<br /> \langle A_1|BA|A_2\rangle=\langle A_1|B\rangle \langle A|A_2\rangle=<br /> \langle A_1|B\rangle A_2=A_2\langle A_1|B\rangle<br />

right?

Thank you.
 
No. You are mixing up operators with bras and kets. It looks like A and B are supposed to be operators. If so, the expressions |A>, <A|, |B>, or <B| make no sense. Operators are neither bras nor kets.
 
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