SOLUTION: The third and sixth terms of a geometric sequence are -75 and -9375 respectively. Find the first term, the common ratio, and an explicit rule for the nth term
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Question 753894: The third and sixth terms of a geometric sequence are -75 and -9375 respectively. Find the first term, the common ratio, and an explicit rule for the nth term Answer by htmentor(1343) (Show Source):
You can put this solution on YOUR website! The formula for the n-th term of a geometric sequence is where a = the first term, and r is the common ratio
We are given 3rd and 6th terms:
Solve for r:
Since this means that the first term, a = -75/25 = -3
The rule for the nth term is