The sum of \[n\] terms of the following series \[1.2+2.3+3.4+4.5+.........\] shall be [MNR 1980]

The sum of \[n\] terms of the following series \[1.2+2.3+3.4+4.5+.....

1.	The sum of \[n\] terms of the following series \[1.2+2.3+3.4+4.5+.........\] shall be [MNR 1980]
A.	\[{{n}^{3}}\]
B.	\[\frac{1}{3}n\,(n+1)(n+2)\]
C.	\[\frac{1}{6}n\,(n+1)(n+2)\]
D.	\[\frac{1}{3}n\,(n+1)(2n+1)\]
Answer» C. \[\frac{1}{6}n\,(n+1)(n+2)\]

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The sum of \[n\] terms of the following series \[1.2+2.3+3.4+4.5+.........\] shall be [MNR 1980]

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