Big Ideas Math Algebra 2, 2014
BI
Big Ideas Math Algebra 2, 2014 View details
1. Defining and Using Sequences and Series
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Exercise 3 Page 409

Practice makes perfect
a Let's start by recalling the definition of arithmetic sequences.

Arithmetic Sequence

A sequence in which the difference between consecutive terms is constant is called an arithmetic sequence.

The terms of an arithmetic sequence with first term a_1 and common difference d can be formed as follows.

a_1 a_1
a_2 a_1+d
a_3 a_2+d
a_4 a_3+d
... ...
a_n a_(n-1)+d
We can conclude that each term in an arithmetic sequence is the sum of the common difference and the previous term. a_1&=a a_n&=a_(n-1)+d

Extra

Example Arithmetic Sequence

Let's investigate the relationship between the terms in the arithmetic sequence with first term a_1=1 and common difference d=1.5.

We can see that each term in this arithmetic sequence is the sum of the common difference 1.5 and the previous term. a_1&=1 a_n&=a_(n-1)+1.5

b Now we will investigate the relationship between the terms in a geometric sequence.

Geometric Sequence

A sequence in which the ratio of any term to the previous term is constant is called a geometric sequence.

The terms of a geometric sequence with first term a_1 and common ratio r can be formed as follows.

a_1 a_1
a_2 r* a_1
a_3 r* a_2
a_4 r* a_3
... ...
a_n r* a_(n-1)
We can conclude that each term in a geometric sequence is the product of the common ratio and the previous term. a_1&=a a_n&=r * a_(n-1)

Extra

Example Geometric Sequence

Let's investigate the relationship between the terms in the geometric sequence with first term a_1=0.5 and common ratio r=2.

We can see that each term in the geometric sequence is the product of the common ratio 2 and the previous term. a_1&=0.5 a_n&=2 * a_(n-1)