# Math Help - chebychev's theorem

1. ## chebychev's theorem

i need to use chebychevs theorem to approximate the number of primes in between two numbers and then calculate how many there actually are
(large numbers, say 5-6 digit)

i understand pi(x)=x/lnx is a good approximation, and that i would use the difference, of the two for how many are in between
i guess i am having trouble with the "theta" part of the expression.

2. Originally Posted by steiner
i need to use chebychevs theorem to approximate the number of primes in between two numbers and then calculate how many there actually are
(large numbers, say 5-6 digit)

i understand pi(x)=x/lnx is a good approximation, and that i would use the difference, of the two for how many are in between
i guess i am having trouble with the "theta" part of the expression.
What is theta, is this big Theta notation?

CB

3. yes, big theta notation