Which of the formula below represents the general terms of the following set of numbers(-1, \(\frac{2}{3}\), -\(\frac{1}{2}\), \(\frac{2}{5}\)......) for n = 1, 2, 3, 4.......?
 

  • A \(\frac{2}{n + 1}\)
  • B (-1)n + 1 \(\frac{2}{n + 1}\)
  • C (-1)n \(\frac{2}{n + 1}\)
  • D \(\frac{n}{2n - 1}\)
  • E (-1)n\(\frac{n}{2n - 1}\)

The correct answer is C. (-1)n \(\frac{2}{n + 1}\)

The general term of the sequence \((-1, \frac{2}{3}, -\frac{1}{2}, \frac{2}{5}, \ldots)\) can be represented by the formula \((-1)^n \frac{2}{n + 1}\).

Here's why:
- For \(n = 1\), the formula gives \((-1)^1 \frac{2}{1 + 1} = -1\), which is the first term of the sequence.
- For \(n = 2\), the formula gives \((-1)^2 \frac{2}{2 + 1} = \frac{2}{3}\), which is the second term of the sequence.
- For \(n = 3\), the formula gives \((-1)^3 \frac{2}{3 + 1} = -\frac{1}{2}\), which is the third term of the sequence.
- For \(n = 4\), the formula gives \((-1)^4 \frac{2}{4 + 1} = \frac{2}{5}\), which is the fourth term of the sequence.

So, the correct answer is \((-1)^n \frac{2}{n + 1}\).

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