A) Statement-1 is false, Statement-2 is true.
B) Statement-1 is true, statement-2 is true; statement-2 is a correct explanation for Statement-1.
C) Statement-1 is true, statement-2 is true; statement-2 is not a correct explanation for Statement-1.
D) Statement-1 is true, statement-2 is false.
Correct Answer: B
Solution :
\[{{T}_{n}}={{(n-1)}^{2}}+(n-1)n+{{n}^{2}}=\frac{{{(n-1)}^{3}}-{{n}^{3}})}{(n-1)-n}\] \[={{n}^{3}}-{{(n-1)}^{3}}\] \[{{T}_{1}}={{1}^{3}}-{{0}^{3}}\] \[{{T}_{2}}={{2}^{3}}-{{1}^{3}}\] \[\vdots \] \[\phi \] \[{{S}_{20}}={{20}^{3}}-{{0}^{3}}=8000\]You need to login to perform this action.
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