CUET Preparation Today
If $σ_k(n)$= Sum of kth powers of all the positive divisors of n, n ∈ N, the what is the value of $σ_2(12)$ ? |
210 216 204 212 |
210 |
The correct answer is option (1) : 210 $σ_2(12)$ Positive divisions of 12 are $ 1, 2,3, 4, 6, 12$ $∴σ_2(12)= 1^2+2^2+3^2+4^2+6^2 +(12)^2$ $=210$ |
