If `(1^2-t_1)+(2^2-t_2)++(n^2-t_n)+=(n(n^2-1))/3` , then `t_n` is equal to `n^2` b. `2n` c. `n^2-2n` d. none of these

If (1^2-t_1)+(2^2-t_2)+......(n^2-t_n)=1/3n(n^2-1) ,then t_n is :(1) n/2 (2) n-1 (3) n+1 (4) n

If 2^(n+4)-2^(n+2)=3, then n is equal to a.0 b.2c.-2d.-1

If m ,n in Na n dm^2-n^2=13 ,t h e n(m+1)(n+1) is equal to a. 42 b. 56 c. 50 d. none of these

If (1+t a n1^0)dot(1+t a n2^0)dot(1+t a n3^0)(1+tan45^0)=2^n , then ' n ' is equal to 16 b. 23 c. 3 0 d. none of these

If (lim)_(x->0)(sin(n x)[(a-n)n x-t a n x])/(x^2)=n (n >0) then the value of ' a ' is equal to 1/n b. n^2+1 c. (n^2+1)/n d. none

If D_k=1nn2k n^2+n+1n^2+n2k-1n^2n^2+n+1a n dsum_(k=1)^n D_k=56. then n equals 4 b. 6 c. 8 d. none of these

(n+2)C_(0)(2^(n+1))-(n+1)C_(1)(2^(n))+(n)C_(2)(2^(n-1))- is equal to

if in a series t_(n)=(n+1)/((n+2)!) then sum_(n=0)^(10)t_(n) equal to