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3 years ago

8

Evaluate the summation of 2 n plus 5, from n equals 1 to 12..

1 answer:

kirza4 [7]3 years ago

4 0

<span>Let f(n) = 2n + 5. Then we must simply calculate (f1), f(2), ..., (f12). And we have that f(1) = 2*1 + 5 <=> f(1) = 7; f(2) = 2*2 + 5 <=> f(2) = 9; f(3) = 2*3 + 5 <=> f(3) = 11. And so on. It's easy to see that the rest of the results will be 13, 15, 17, 19, 21 and so on. So the summation will be S = 7 + 9 + 11 +... + 29 <=> S = 216</span>

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Step-by-step explanation:

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Read 2 more answers