The first term of a geometric sequence is and the third term is , with all terms positive. What is the 5th term?

Answer and explanation

Correct answer: A.

  1. Step 1: with gives , so (positive terms).
  2. Step 2: The terms are .
  3. Step 3: The 5th term is .
Answer
.
Why not the others: : is the 4th term. : treats the sequence as arithmetic with difference . : is the 6th term.

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