help

[sleek scroll]

For the 17th question. I got how to do it but how do I know when shall I stop checking values for n like how do I know n=64737(random value) will not satisfy or not satisfy the eqn

[reef aurora]

You dont need to check values of n

it says 'for some positive integer n'

C should vary depending on n

that means you leave C in terms of n

so if you did the algebra correctly that expression for C in the box should be the answer

unless JEE only has numerical answers idk

oh sorry it might mean across all possible values of n

in which case it becomes a question of when does (2^n - 1 - 2n) divide 2n(n-1)

[sleek scroll]

How do I solve that cuz like that's basically what the question in asking

[reef aurora]

I’m terrible with number theory

idk

Well you know that 2^n grows quickly

The denominator grows much faster than the numerator

So u only have to check small n

Because they’re sequences of integers

So c has to be an integer

u can stop checking after 7

7 is when the denominator > numerator

So u can’t get integers including and after that

[sleek scroll]

Ohh well makes sense thanks

.close