11.2 Arithmetic Series
What is a series? When the terms of a sequence are added, the indicated sum of the terms is called a series. Example Sequence 1, 2, 3, 4, 5, 6 Series
Sum of an Arithmetic Series
Find the sum of the series …+52 n = 10
Find the sum of the first 50 positive even integers
Aiden did pushups every day in January. He started on January 1 st and increased the number of pushups done each day by 1. He did a total of 1085 pushups for the month. How many pushups did he do on the first day?
Find the first three terms a 1 = 9 a n = 105 S n = 741 Step 1: plug in to find n Step 2: plug in to find d Step 3: use d to find the terms
Sigma Notation Compact form for series Uses the summation symbol Σ Greek letter sigma
Sigma Notation formula for the sequence Last value of n First value of n
Ex: For the sequence 1, 2, 3, 4, 5, 6 a 1 = 1 d = 1 a n = 1 + (n – 1)1 a n = 1 + n – 1 a n = n
Find the sum 8 n=1 5-2n
Find the sum 150 k= k