The \[{{n}^{th}}\] term of series \[\frac{1}{1}+\frac{1+2}{2}+\frac{1+2+3}{3}+.......\] will be [AMU 1982]

The \[{{n}^{th}}\] term of series \[\frac{1}{1}+\frac{1+2}{2}+\frac{1+

1.	The \[{{n}^{th}}\] term of series \[\frac{1}{1}+\frac{1+2}{2}+\frac{1+2+3}{3}+.......\] will be [AMU 1982]
A.	\[\frac{n+1}{2}\]
B.	\[\frac{n-1}{2}\]
C.	\[\frac{{{n}^{2}}+1}{2}\]
D.	\[\frac{{{n}^{2}}-1}{2}\]
Answer» B. \[\frac{n-1}{2}\]

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The \[{{n}^{th}}\] term of series \[\frac{1}{1}+\frac{1+2}{2}+\frac{1+2+3}{3}+.......\] will be [AMU 1982]

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