MA.FR.3.c: Determine the 𝑛ᵗʰ term, 𝑎ₙ, for an arithmetic or geometric sequence.

Determine the 𝑛ᵗʰ term, 𝑎ₙ, for an arithmetic or geometric sequence.

Example Problems

Find the sum:

\sum_{k = 0}^{60} (4 - 3k) =

Find the sum:

\sum_{k=1}^{40} 2(-0.8)^{k-1}

Find the sum:

\sum_{k = 5}^{45} (3k - 28) =

Khan Academy Resources

Use arithmetic sequence formulas Use geometric sequence formulas Geometric series formula Evaluate sequences in recursive form Arithmetic series formula Arithmetic series intro Arithmetic sequence problem Using recursive formulas of geometric sequences Worked example: using recursive formula for arithmetic sequence Using explicit formulas of geometric sequences Evaluating sequences in recursive form Geometric series word problems: hike

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