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Topic: when is sqrt(a/b) not the same as sqrt(a)/sqrt(b) ?
Replies: 8   Last Post: Mar 5, 2014 3:34 PM

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 D Herring Posts: 62 Registered: 8/23/06
Re: when is sqrt(a/b) not the same as sqrt(a)/sqrt(b) ?
Posted: Mar 4, 2014 9:16 PM

On 03/01/2014 07:54 PM, Richard Fateman wrote:

> Isn't it possible that sqrt(4) has 2 values, sqrt(-4) has 2 values as well?

+2...

-2...

+2...

-2....

Nope. +2 for me!

:)

Honestly, the way math was taught in school, to this day it is easy
for me to see x^2 but hard to see both branches of sqrt(x) for
positive x -- even though they are essentially the same curves. I
think it was all the emphasis on functions having a single output
value for a given input. If sqrt(x) is a function, then...

- Daniel

Date Subject Author
3/1/14 Nasser Abbasi
3/1/14 Nasser Abbasi
3/2/14 G. A. Edgar
3/2/14 Richard Fateman
3/1/14 Axel Vogt
3/1/14 Richard Fateman
3/4/14 D Herring
3/5/14 Richard Fateman
3/5/14 Axel Vogt