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Find the nth term of the following sequence 5,20,45,80,125

User Theopap
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2 Answers

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Final answer:

The nth term of the sequence 5, 20, 45, 80, 125 is a quadratic expression. The sequence reflects consecutive differences of multiples of 5, which supports a quadratic nature. The nth term is defined by the formula Tn = n^2 + 4n.

Step-by-step explanation:

To find the nth term of the given sequence (5, 20, 45, 80, 125), we need to determine a pattern or rule that generates these terms. Observing the differences between consecutive terms, we get:

  • 20 - 5 = 15
  • 45 - 20 = 25
  • 80 - 45 = 35
  • 125 - 80 = 45

The differences are consecutive multiples of 5, indicating this is a sequence of quadratic nature. The nth term can be represented by a quadratic expression of the form an2 + bn + c. Using the data points and solving a system of equations, we can find that the nth term is defined by:

Tn = n2 + 4n

User Kensen John
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5 votes

Answer:

{5, 20, 45, 80, 125} = 5{1, 4, 9, 16, 25} = 5{1², 2², 3², 4², 5²}

→ U{n} = 5n²

Step-by-step explanation:

User Maczniak
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