# Solving an interval for s^2

• March 12th 2011, 12:01 PM
iBurger
Solving an interval for s^2
http://i56.tinypic.com/2rzxhg9.jpg

I'm trying to understand what's happening here, and particurlarly why the signs change. I think: "take all sides to the power ^-1". But then the signs shouldn't change... i'm so perplexed ;)
• March 12th 2011, 12:06 PM
skeeter
let's look at something a bit simpler ...

note that $\dfrac{1}{2} > \dfrac{1}{3}$

now, what is the relationship between their reciprocals?
• March 12th 2011, 12:13 PM
iBurger
Quote:

Originally Posted by skeeter
let's look at something a bit simpler ...

note that $\dfrac{1}{2} > \dfrac{1}{3}$

now, what is the relationship between their reciprocals?

Wait: do you suggest that if you take something to the power minus one [ c^-1] the relationship relative to other value changes as well.

so,

4 > 3
1/4 < 1/3

Aha!
• March 12th 2011, 01:00 PM
iBurger
I'm pretty sure that's it. Thank you!