If `N` denotes the set of all positive integers and if `f : N -> N` is defined by `f(n)=` the sum of positive divisors of `n` then `f(2^k*3)`, where k is a positive integer isA. `2^(k+1) -1`B. `2(2^(k+1)-1)`C. `3(2^(k+1)-1)`D. `4(2^(k+1)-1)`

If `N` denotes the set of all positive integers and if `f : N -> N` is

1.	If `N` denotes the set of all positive integers and if `f : N -> N` is defined by `f(n)=` the sum of positive divisors of `n` then `f(2^k*3)`, where k is a positive integer isA. `2^(k+1) -1`B. `2(2^(k+1)-1)`C. `3(2^(k+1)-1)`D. `4(2^(k+1)-1)`
Answer» Correct Answer - C

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If `N` denotes the set of all positive integers and if `f : N -> N` is defined by `f(n)=` the sum of positive divisors of `n` then `f(2^k*3)`, where k is a positive integer isA. `2^(k+1) -1`B. `2(2^(k+1)-1)`C. `3(2^(k+1)-1)`D. `4(2^(k+1)-1)`

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