Most Important Selected Qs for JEE AdvancedMathematicsSequences and Series
Find the value of 1+ 1 1^2 + 1 2^2 + 1+ 1 2^2 + 1 3^2 + 1+ 1 3^2 + 1 4^2 + + 1+ 1 2010^2 + 1 2011^2
Options
- A2011- 1 2011
- B2011+ 1 2011
- C2011- 1 2010
- Dnone of these
Correct answer
A. 2011- 1 2011
Step-by-step solution
T_n= 1+ 1 n^2 + 1 (n+1)^2 = n^4+2 n^3+n^2+n^2+2 n+1+n^2 n^2(n+1)^2 = n^2+n+1 n(n+1) =1+ 1 n(n+1)