Hi, can someone please tell me whether or not I can switch the 'order' of the indices over which a double sum is taken? To clarify, my question is whether or not the following is true.(adsbygoogle = window.adsbygoogle || []).push({});

[tex]

\sum\limits_{j = 1}^n {\sum\limits_{i = 1}^n {\left( {a_i b_j } \right)} } \mathop = \limits^? \sum\limits_{i = 1}^n {\sum\limits_{j = 1}^n {\left( {a_i b_j } \right)} }

[/tex]

Any help would be appreciated.

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# Homework Help: Summation notation

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