Paper 1 · Sequences and Series ⏱ Tested in 5+ recent exam questions Lesson 3 of 7

LCOL Sequences and Series 3: Sn for an arithmetic Pattern

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You’ll learn

  • Build the sum formula Sₙ = (n/2)[2a + (n − 1)d]
  • Add up the first n terms of an arithmetic pattern

Formula used

Sum of a linear pattern

Sₙ = (n/2)[2a + (n - 1)d]

On page 22 of the log tables — read it off, don’t memorise.

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