Answer :
The rule is n/(-2)
What is geometric Progression?
A geometric progression is a sequence in which any element after the first is obtained by multiplying the preceding element by a constant called the common ratio which is denoted by r.
Given:
64, -32,16,-8
r= 64/-32
r= -2
again, r= -32/16
r= -2
By above we concluded that the common ratio is is -2.
If n is natural numbers for finding geometric progression the rule which defines it n/(-2).
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