Learn about sequences in algebra with Khan Academy's Unit 9, including arithmetic and geometric sequences.

Learn how to write explicit formulas for arithmetic sequences on Khan Academy.

Learn about arithmetic sequences with free educational videos on Khan Academy.

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Learn about exponential growth functions with Khan Academy's comprehensive and engaging course.

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Given the formula of an arithmetic sequence, either in explicit form or in recursive form, find a specific term in the sequence.

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Sal introduces arithmetic sequences and their main features, the initial term and the common difference. He gives various examples of such sequences, defined explicitly and recursively.

Sal finds an explicit formula of a geometric sequence given the first few terms of the sequences. Then he explores equivalent forms the explicit formula and finds the corresponding recursive formula.