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The first,third and fifth term of a geometric sequence forms an arithmetic sequence.If the first term of the sequence is 3. Find the 10th term of the geometric sequence

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r = 3 and the 10th term of the geometric sequence is 19,683.

Let the common ratio of the geometric sequence be r.

The third term of the geometric sequence is 3r.

The fifth term of the geometric sequence is 3r^2.

Since the first, third, and fifth terms form an arithmetic sequence, we have:

3 + 3r = 2(3r^2)

3 + 3r = 6r^2

6r^2 - 3r - 3 = 0

r^2 - r/2 - 1 = 0

(r - 3)(r + 1/2) = 0

r = 3 or r = -1/2

If r = 3, then the 10th term of the geometric sequence is 3(3)^9 = 19,683

If r = -1/2, then the 10th term of the geometric sequence is 3(-1/2)^9 = -3/256

Since the first term of the sequence is 3, the common ratio must be positive. Therefore, r = 3 and the 10th term of the geometric sequence is 19,683.

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