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Lesson 13: The Sum of n Terms of a Geometric Series
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Sum of First n Terms of an Arithmetic Series
Lesson 13 · The Sum of n Terms of a Geometric Series
Sum of First n Terms of an Arithmetic Series
Optional Mathematics
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8 min
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Question 1 of 14
1
Which formula gives the sum of the first n terms of an arithmetic series when the first term a and the last term l are known?
\( n(a+l) \)
\( \frac{n}{2}(a-l) \)
\( \frac{n}{2}(a+l) \)
\( \frac{a+l}{2n} \)