21.2 Geometric sequences

Geometric sequences

A geometric sequence, also called geometric progression, is a number sequence with a common ratio between successive terms. A term in a geometric sequence can be found by multiplying the previous one by a non-zero and fixed number (a common ratio).

Lessons

Notes:
• geometric sequence: a sequence with a common ratio between successive terms.
• the nth term, tn{t_n} ,of a geometric sequence:
tn=t1rn1{t_n}\; = \;{t_1} \cdot {r^{n - 1}}
where, tn{t_n} : nth term
t1{t_1} : first term
r : common ratio
  • 1.
    Geometric sequence formula
    Consider the geometric sequence: 2, 6, 18, 54, … .
Teacher pug

Geometric sequences

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