CAT Exam Model Paper 7 with solutions for free online practice

The general term is of the form $\frac{\left(\mathrm{X}+\mathit{n}\left(\mathit{n}+2\right)\right)}{\left(\mathit{n}+2\right)}$
n(n + 2) is always divisible by (n + 2). So we can say that n(n + 2) ± 1 would never be divisible by (n + 2). If we put X = -1, the numerator and denominator of all the terms would be co-prime.