Suppose `A` is a complex number and `n in N ,` such that `A^n=(A+1)^n=1,` then the least value of `n` is `3` b. `6` c. `9` d. `12`

IF 1+2+3+………..+n=78, then the value of n is:

If .^(20)C_(n+1) = ^ (n) C_(16) , then the value of n is

If .^(n)P_(3)+.^(n)C_(n-2)=14n , the value of n is

If .^(2n)C_(3):^(n)C_(3)=11:1 , find the value of n.

If ,^(n) P_r=^n P_(r+1) and ^n C_r=^n C_(r-1,) then the value of n+r is.

If omega be a cube root of unity and (1+omega^(2))^(n)=(1+omega^(4))^(n) , then the least positive value of n is

If S denotes the sum to infinity and S_(n) , the sum of n terms of the series 1+( 1)/(2) +( 1)/( 4) + ( 1)/( 8 ) +"………….", such that S-S_(n) lt ( 1)/( 1000) , then the least value of n is :

If S_n = 1+1/2 + 1/2^2+...+1/2^(n-1) and 2-S_n < 1/100, then the least value of n must be :

If (a^(n)+b^n)/ (a^(n-1) +b^(n-1)) is the A.M. between a and b, then find the value of n.

If (a^(n)+b^(n))/(a^(n-1)+b^(n-1)) is an G.M between a and b then the value of n is