Does the Matrix \(\frac{0|w^{2}}{w|0}\) Have to Be an Element of the Group?

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Homework Statement


According to wikipedia, one of the requirements of group is:
For all a, b in G, the result of the operation, a • b, is also in G.

So say we have 2 (2x2) matricies as elements of a group:
\frac{0|1}{1|0} and \frac{w|0}{0|w^{2}}
and the product \frac{0|1}{1|0} • \frac{w|0}{0|w^{2}} is \frac{0|w^{2}}{w|0}

does this mean that the matrix \frac{0|w^{2}}{w|0} also has to be an element of that group or does it mean that the elements of the matrix itself (0,w,w^{2}) have to just generally exist?
 
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"the result of the operation, a • b, is also in G" is pretty unambiguous. It has to be an element of the group.
 
hi xago! :wink:
xago said:
does this mean that the matrix \frac{0|w^{2}}{w|0} also has to be an element of that group …

yes :smile:
 
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