study the convergence of the following series indicating the radius of convergence and the interval of convergence
i)
ii)
please i need help with this to understand how to do it D:
When you've written "sen", i believe you meant "sin". If that is so, you can try working on the function. You should check out the formula
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After that, you gotta remember what the criteria for convergence of sums like [LaTeX ERROR: Convert failed] are. Also, what formulas involving [LaTeX ERROR: Convert failed] and limits do you have?