Hi,
In this math, can we choose the answer from options ?I mean if the denominator matches the number (1/15)mentioned in the question,can we consider that will be the answer since taking values for n everytime is time-consuming.
I mean the product of f(n) from 1 to n is indeed \frac{1}{2n + 1}, so yes you’re looking for the least value of n such that 2n + 1 \geq 15