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Lesson 3A: Arithmetic Sequences. Ex 1: Can you find a pattern and use it to guess the next term? A) 7, 10, 13, 16,... B) 14, 8, 2, − 4, ... C) 1, 4, 9, 16,. Definition: . An arithmetic sequence is a sequence made by adding or subtracting the same value each time. Explicit Formula.
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Ex 1: Can you find a pattern and use it to guess the next term? A) 7, 10, 13, 16,... B) 14, 8, 2, − 4, ... C) 1, 4, 9, 16,...
Definition: • An arithmetic sequence is a sequence made by adding or subtracting the same value each time.
Explicit Formula • a, a + d, a + 2d, a + 3d … • d = common difference • a = 1st term • nth term:
Ex 2: So which examples were arithmetic sequences? Identify d and a. Write the formula for an. • A) 7, 10, 13, 16,... • B) 14, 8, 2, − 4, ... • C) 1, 4, 9, 16,...
Ex 3: The formuladescribes an arithmetic sequence. What are the first 4 terms in the sequence?
Ex 4: Find the first 4 terms and the nth term: a = 2 & d = 3a1= a2= a3= a4=an=
Ex 5: Write an explicit formula for the following sequence: 9, 4, –1, –6, –11, … a = d = an =
Recursive Formula • A recursive formula is a formula that expresses any term an in terms of the previous term an−1
Ex 6: Write a recursive formula for the following sequence: • -2, -6, -10, -14, …
Cool Math! • https://www.youtube.com/watch?v=wTlw7fNcO-0 • https://www.youtube.com/watch?v=SjSHVDfXHQ4 • https://www.youtube.com/watch?v=ahXIMUkSXX0