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Algebra (all content)

Course: Algebra (all content) > Unit 18

Lesson 6: Advanced sigma notation
Math
Algebra (all content)
Series & induction
Advanced sigma notation
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Arithmetic series in sigma notation

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Problem

The series 2+5+8+…+371+374 can be written using sigma notation (also called summation notation):
∑k=1nak
Write an expression for ak in terms of k.
ak=
Find n.
n=
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi
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