2. 1.1 Arithmetic Sequences and Series Warm-up (IN) 1.A pyramid of logs has 2 logs in the top row, 4 logs in the second row from the top, 6 logs in the third row from the top, and so on, until there are 200 logs in the bottom row. a.What is the # of logs in each of the first 12 rows? b.What is the total # of rows of logs? c.How many logs are in the 76 th row from the top? d.What is the total # of logs in the pyramid? Learning Objective: to understand what an arithmetic sequence is and how to find the terms. 100 2,4,6,8,10,12,14,16,18,20,22,24 152 10,100

3. Notes! Arithmetic Sequence – A sequence of #s where the difference between any two consecutive terms is a constant Common difference (d) - the constant between each term Ex 1 – Are the following sequences arithmetic? a. 3, 7, 11, 15, 19, … yes d=4 b. 5, 3, 1, -1, -3, … yes d=-2 c. 1, 4, 9, 16, 25, … no d. 2, 4, 8, 16, … no

4. Ex 2 – find the next 3 terms a. 14, 18, 22, 26, ____, ____, ____ 30 34 38 b. 3, -3, -9, -15, ____, ____, ____ -21 -27 -33 c. -3, 1, 5 To find the term of an arithmetic sequence with the first term and the common difference d Ex 3 – write a rule for the term a. 3, 8, 13, 18, …

5. b. 5, 1, -3, -7, … Ex 4 – write the first 3 terms if a. b.

6. HW – worksheet #s 1-22 Out – find the 25 th term of the sequence 4,10,16,22, … Summary – This lesson is easy (or hard) because… Don’t forget about POW!!