Author Topic: p1 cie question  (Read 779 times)

Offline cooldude

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p1 cie question
« on: March 18, 2010, 02:55:00 pm »
why is root x always postive, for example why do we consider root 4=2 and not +/-2.

Offline astarmathsandphysics

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Re: p1 cie question
« Reply #1 on: March 18, 2010, 03:31:54 pm »
There are 2 roots. Why do you ask this

Offline cooldude

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Re: p1 cie question
« Reply #2 on: March 18, 2010, 04:51:20 pm »
There are 2 roots. Why do you ask this

because our book says this, for example when x^0.5-6-x
we get x=4,9
they say root x=3,2
and since 6-9=-3 they say that 9 does not satisfy the original equation as they are not considering root x=-3, as they say that root x=>0, so i am asking why is root x=>0?

Offline astarmathsandphysics

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Re: p1 cie question
« Reply #3 on: March 18, 2010, 07:07:53 pm »
Only because the question says or because x is b length for example:)