Algebra Examples

Identify the Sequence 2 , 6 , 18 , 54
2 , 6 , 18 , 54
Step 1
This is a geometric sequence since there is a common ratio between each term. In this case, multiplying the previous term in the sequence by 3 gives the next term. In other words, an=a1rn-1.
Geometric Sequence: r=3
Step 2
This is the form of a geometric sequence.
an=a1rn-1
Step 3
Substitute in the values of a1=2 and r=3.
an=23n-1
2, 6, 18, 54
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