JAMB - Mathematics (1980 - No. 17)
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.......?
\(\frac{2}{n + 1}\)
(-1)n + 1 \(\frac{2}{n + 1}\)
(-1)n \(\frac{2}{n + 1}\)
\(\frac{n}{2n - 1}\)
(-1)n\(\frac{n}{2n - 1}\)
설명
(-1, \(\frac{2}{3}\), -\(\frac{1}{2}\), \(\frac{2}{5}\)......)
nthterm is (-1)n\(\frac{2}{n + 1}\)
Since (-1)n will always be negative for n = odd
nthterm is (-1)n\(\frac{2}{n + 1}\)
Since (-1)n will always be negative for n = odd