Sigma n2
Trending Questions
Q. Find nth term and sum of nth term of the sequence 2, 5, 12, 31, 86.....
Q. The value of 1002−992+982−972.........−32+22−12 is:
- 5050
- 4950
- 5000
- 25000
Q.
The sum of infinite terms of the series where is a constant is
infinity
None of these
Q. Find the sum of the series (33−23)+(53−43)+(73−63)+...... to 10 terms.
Q. The series of natural numbers is divided into groups (1), (2, 3, 4), (3, 4, 5, 6, 7), (4, 5, 6, 7, 8, 9, 10), ... Find the sum of the numbers in nth group.
- [n+1]2
- [2n−1]2
- [n−1]2
- [2n+1]2
Q. Each of these questions contains two statements, Statement 1(Assertion) and Statement 2(Reason).
Statement-I : If sum of n terms of a series is 6n2+3n+1, then the series is in A.P.
Statement-II : Sum of n terms of an A.P. is always of the form an2+bn, where a and b are constant.
State which of the following is correct :
(A) Statement-I is true, Statement-II is true ; Statement-II is correct explanation for Statement-I.
(B) Statement-I is true, Statement-II is true ; Statement-II is NOT a correct explanation for Statement-I
(C) Statement-I is true, Statement-II is false
(D) Statement-I is false, Statement-II is true
(B) Statement-I is true, Statement-II is true ; Statement-II is NOT a correct explanation for Statement-I
(C) Statement-I is true, Statement-II is false
(D) Statement-I is false, Statement-II is true
- D
- B
- A
- C
Q. Find the sum of n terms of the series 11.3+21.3.5+31.3.5.7+41.3.5.7.9+...
Q. The series 11.2+12.3+13.4+...to∞ has the sum=?
- ∞
- 1
- 23
- 2
Q. The sum of the first 10 terms of the series 9+99+999+..... is
- 109−1
- 98(910−1)
- 1009(1010−1)
- 1009(109−1)
Q.
Find the sum of the series 22 + 42 + 62 + 82 +................ 20 terms
Q. The nth term of a sequence is 3n−2. Is the sequence an A.P. If so find its rth term.
Q. Sum the following series to n terms and to infinity 11.4+14.7+17.10+....
Q.
The sum to n terms of the series 1 + 3 + 7 + 15 + . . . . . .
Q. In the sum of first n terms of an A.P. is cn2. then the sum of squares of these n terms is
- n(4n2−1)c26
- n(4n2−1)c23
- n(4n2+1)c23
- n(4n2+1)c26
Q. Find the sum of n terms off the series 2+5+12+31+86+.....