Get answer: Use the formula for the sum of the first n integers and/or the formula for
Chapter 5, Problem 24(choose chapter or problem)
"""Use the formula for the sum of the first n integers and/or the formulafor the sum of a geometric sequence to evaluate the sumsin 20–29 or to write them in closed form.1 + 2 + 3+· · ·+(k ? 1), where k is an integer and k ? 2.Unfortunately, we don't have that question answered yet. But you can get it answered in just 5 hours by Logging in or Becoming a subscriber.
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