Sequences & Series · Sequences
Arithmetic Sequence
Each term is obtained by adding a constant difference d to the previous term. Always diverges (unless d = 0).
Worked examples
Find the 10th term of 3, 7, 11, 15, ...
- a₁ = 3, d = 4. a₁₀ = 3 + 9(4) = 39
Answer: 39
Find d if a₁ = 5 and a₅ = 17.
- 17 = 5 + 4d → d = 3
Answer: d = 3
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