Superstring Theory problem. Infinitesimal supersymmetry transofrmations

B3NR4Y
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Homework Statement


Let
\begin{equation}
\delta _{1} \, and \, \delta _{2}
\end{equation}
be two infinitesimal sypersymmetry transformations on xμ compute
\begin{equation}
[\delta _{1}, \delta _{2} ]x^{μ}.
\end{equation}


Homework Equations


The commutator is:
\begin{equation}
[\delta _{1}, \delta _{2} ]x^{μ}=\delta_{1}\delta_{2} x^{μ} - \delta_{2}\delta_{1} x^{μ}
\end{equation}


The Attempt at a Solution


I am able to get the first term, but the second term trips me up
\begin{equation}
\begin{split}
\delta_{1}\delta_{2} &= \delta_{1}( i\bar{\epsilon}^{A}_{2} \Gamma^{μ}\theta^{A})\\
& =i\bar{\epsilon}^{A}_{2} \Gamma^{μ}\delta_{2} \theta^{A}\\
& =i\bar{\epsilon}^{A}_{2} \Gamma^{μ}\theta^{A}
\end{split}
\end{equation}
 
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It would be helpful if you told us what book/lecture notes you are reading, so we could get an idea on what the heck you're trying to do.
 
I'm working from the book 'String Theory Demystified' apparently, answers are not given (or were torn out by the previous person to own it). It asked me to compute
\begin{equation}
[\delta_{1} , \delta{2}] x^{μ}
\end{equation}
It then told me that the commutator was [δ1,δ2]xμ=δ1δ2xμ−δ2δ1xμ
[\delta_{1},\delta_{2}]x^{μ}=\delta_{1}\delta_{2}x^{μ}-\delta_{2}\delta_{1}x^{μ}
I'm trying to compute the second term, but I can't seem to do it. I already computed the first term in the original post
 
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