10. Sequence = a number pattern Term = each number in a sequence Arithmetic Sequence = a sequence where a fixed number is added to each previous term. Common Difference = the fixed number Example -4, 4, 12, 20 +8 +8 +8 Common Difference of Sequence is 8
11. Find the common difference of each arithmetic sequence. a. 5, 2, -1, -4 b. 8, 11, 14, 17
12. The rule for an Arithmetic Sequence is: A( n ) = a + ( n - 1) d A(n ) = nth term a = first term n = term number d = common difference We can use this rule to find the value of any given term.
13. Example Find the first, fifth and tenth term of the sequence that has the rule A( n ) = 12 + ( n - 1)(-2) First term A(1) = 12 + (1 - 1)(-2) A(1) = 12 Fifth term A(5) = 12 + (5 - 1)(-2) A(5) = 12 + (4)(-2) A(5) = 12 + -8 = 4 Tenth term A(10) = 12 + (10 - 1)(-2) A(10) = 12 + (9)(-2) A(10) = 12 + -18 = -6