# Infinite Surd Help

• May 2nd 2009, 10:51 AM
bookjunkie24
Infinite Surd Help
Hi there, first time poster here.

I'm having trouble with infinite surds.
I understand that as $n$ approches infinity $an -an+1$ approaches zero.
I understand that the limit of the sequence is the exact value of the infinite surd.
I also know how to solve the surd by setting it equal to x and using quadratics.

But what I don't understand is how to connect any of it. I can't explain how to get from $an -an+1$ to the exact value.

In other words, I'm at point A and I know where point B is, I just don't know how to get there.
• May 2nd 2009, 12:46 PM
Sodapop
I'll simply redirect you toward the following thread: http://www.mathhelpforum.com/math-he...nite-surd.html

Hope this helps!
• May 2nd 2009, 01:32 PM
bookjunkie24
I appreciate the help, but I already knew about that method. What I don't understand is how I'm supposed to reach that method using only http://www.mathhelpforum.com/math-he...8b5b96b1-1.gif=0 as n approaches infinity.
• May 2nd 2009, 04:46 PM
mr fantastic
Quote:

Originally Posted by bookjunkie24
I appreciate the help, but I already knew about that method. What I don't understand is how I'm supposed to reach that method using only http://www.mathhelpforum.com/math-he...8b5b96b1-1.gif=0 as n approaches infinity.

The equation you're posting makes no sense: an - an = 0 ..... Please post the correct equation using appropriate notation.