MDHS Precalculus 9.2Recommended reading: Section 9.2 in text. Arithmetic Sequences and Partial SumsObjectives: 1.Recognize, write, and find the terms of arithmetic sequences.thn2.Find partial sums of arithmetic sequences.thnArithmetic Sequences A sequence whose consecutive terms have a common difference is called an arithmetic sequence. Example 1 Arithmetic Sequences The sequence whose term is is arithmetic. For this sequence, the common differencethnn4+ 3between consecutive terms is 4.Find the first 5 terms.
Example 2 Finding the TermthnFind a formula for the term of the arithmetic sequence whose common difference is 3 andthnwhose first term is 2. Example 3 Using a Recursion Formula Find the ninth term of the arithmetic sequence that begins with 2 and 9. The Sum of a Finite Arithmetic Sequence There is a formula for the sum of a finite arithmetic sequence.
Example 3 Sum of a Finite Arithmetic Sequence Find the sum: 1+3+5+7+9+11+13+15+17+19 By calculator: By the equation: Example 4