DQ Thurs 330 Arithmetic Sequence An arithmetic sequence

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DQ – Thurs 3/30

DQ – Thurs 3/30

Arithmetic Sequence An arithmetic sequence is defined as a sequence in which there is

Arithmetic Sequence An arithmetic sequence is defined as a sequence in which there is a common difference between consecutive terms. Comm on Differe nce = 5

Is the given sequence arithmetic? If so, identify the common difference. 1. 2. 3.

Is the given sequence arithmetic? If so, identify the common difference. 1. 2. 3. 4. 2, 4, 8, 16, … 4, 6, 12, 18, 24, … 2, 5, 7, 12, … 48, 45, 42, 39, …

Arithmetic Sequence Formula The 1 st number in the sequence. The common difference. an

Arithmetic Sequence Formula The 1 st number in the sequence. The common difference. an = a 1 + (n – 1) • d The “nth” number in the sequence. Ex. a 5 is the 5 th number in the sequence. The same as the n in an. If you’re looking for the 5 th number in the sequence, n = 5.

Example 1: an = a 1 + (n – 1) • d Given the

Example 1: an = a 1 + (n – 1) • d Given the sequence -4, 5, 14, 23, 32, 41, 50, …, find the 14 th term.

Example 3: an = a 1 + (n – 1) • d Given the

Example 3: an = a 1 + (n – 1) • d Given the sequence 81, 80. 5, 80, 79. 5, 79, …, find the 9 th term.

Example 4: an = a 1 + (n – 1) • d Given the

Example 4: an = a 1 + (n – 1) • d Given the sequence 79, 75, 71, 67, 63, …, find the term number that is -169.

Example 5: an = a 1 + (n – 1) • d Suppose you

Example 5: an = a 1 + (n – 1) • d Suppose you are saving up for a new gaming system. You have 100 dollars this year, and you plan to add 33 dollars each of the following years. How much money will you have in 7 years?

Geometric Sequences An geometric sequence is defined as a sequence in which there is

Geometric Sequences An geometric sequence is defined as a sequence in which there is a common ratio between consecutive terms. Comm on Ratio = 2

Is the given sequence geometric? If so, identify the common ratio. 1. 2. 3.

Is the given sequence geometric? If so, identify the common ratio. 1. 2. 3. 4. 5. 5, 15, 45, 135, … 15, 30, 45, 60, … 6, -24, 96, -384, … 7, 0. 07, 0. 007, … 10, 4, 1. 6, 0. 64, …

Geometric Sequence Formula 1 st The number in the sequence. The same as the

Geometric Sequence Formula 1 st The number in the sequence. The same as the n in an. If you’re looking for the 5 th number in the sequence, n = 5. an = a 1 • r The “nth” number in the sequence. Ex. a 5 is the 5 th number in the sequence. (n-1) The common ratio.

Example 1: an = a 1 • r (n-1) Given the sequence 4, 28,

Example 1: an = a 1 • r (n-1) Given the sequence 4, 28, 196, 1372, 9604, …, find the 14 th term.

Example 2: an = a 1 • r (n-1) Given the sequence -2, 6,

Example 2: an = a 1 • r (n-1) Given the sequence -2, 6, -18, 54, -162, …, find the 17 th term.

Example 3: an = a 1 • r (n-1) Given the sequence 100, 83,

Example 3: an = a 1 • r (n-1) Given the sequence 100, 83, 68. 89, 57. 1787, …, find the 9 th term.

Example 5: an = a 1 • r (n-1) Suppose you want a reduced

Example 5: an = a 1 • r (n-1) Suppose you want a reduced copy of a photograph. The actual length of the photograph is 10 in. The smallest size the copier can make is 64% of the original. Find the length of the photograph after five reductions.