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Find the common ratio of the geometric sequence 9, -18, 36,...

User Joelhardi
by
3.3k points

2 Answers

2 votes

Answer:

-2

Explanation:

Each term is multiplied by -2 to get the next term

User Kirti Nikam
by
3.5k points
3 votes

Answer:

Explanation:

All even members of the sequence are -

All odd members of the sequence are +

Ignore that for the moment and let's just find the ratio.

t_n/t_n-1 = - 2

t_2/t_n-1 = -18/9 = - 2

t_3/t_2 = 36/-18 = - 3

User Hazrelle
by
3.7k points