Help please and explanation please
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For this case we must add the given series. We expanded the series for each of the values of i, that is, from 1 to 5:[tex]3 (1) +3 (2) +3 (3) +3 (4) +3 (5) =\\3 + 6 + 9 + 12 + 15 =[/tex]
We add the terms:
[tex]9 + 9 + 12 + 15 =\\18 + 12 + 15 =\\30 + 15 =\\45[/tex]
Finally, the value of the given series is 45.
Answer:
45