1. Help! Calculus Proof

Suppose delta > 0

Prove that there exists a positive integer n such that

0 < 1/(4n+1)pi/2 < delta

and sin( (4n+1)pi)/2) = 1

How do you do this?

2. Originally Posted by Sterwine
Suppose delta > 0
Prove that there exists a positive integer n such that
0 < 1/(4n+1)pi/2 < delta
and sin( (4n+1)pi)/2) = 1
It is very hard to read you post. I assume that it is $\frac{1}{\frac{(4n+1)\pi}{2}}$

Do you understand that the sequence $\left(\frac{2}{(4n+1)\pi}\right)\to 0$?
Then if $\delta >0$ that almost all of the terms of that sequence are less than $\delta$.

3. I think the denominator is (4n+1) times Pi/2

4. Originally Posted by Sterwine
I think the denominator is (4n+1) times Pi/2
You do understand that $(4n+1)\cdot \frac{\pi}{2}=\frac{(4n+1)\pi}{2}?$

5. yes, yes I do