Sequences as Functions
Aligned to F-IF.A.3 — Common Core State Standards for Mathematics.
What this lesson teaches
A sequence is a function whose inputs are whole-number positions (1, 2, 3, …) and whose outputs are the terms. It can be given by a formula or defined recursively from the previous term.
Worked example
A sequence starts at 5 and adds 3 each time: a(1) = 5 and a(n) = a(n−1) + 3. Then a(2) = 8, a(3) = 11, and a(4) = 14.
Practice questions
- List the first four terms of a(n) = 2n + 1.
- A sequence has a(1) = 10 and a(n) = a(n−1) − 4. Find a(2) and a(3).
- Write a recursive rule for the sequence 3, 6, 9, 12, ….
Watch the lesson
Every lesson comes with a video taught in English and Spanish — the same video the QR code in the printed workbook opens.
▶ Watch this lessonEn español
Sucesiones como Funciones
Una sucesión es una función cuyas entradas son posiciones enteras (1, 2, 3, …) y cuyas salidas son los términos. Se puede dar con una fórmula o definir de forma recursiva a partir del término anterior.
Ejemplo: Una sucesión empieza en 5 y suma 3 cada vez: a(1) = 5 y a(n) = a(n−1) + 3. Entonces a(2) = 8, a(3) = 11 y a(4) = 14.
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