Velocity Reviews > can x^2 + y^2 = square root of -4?

# can x^2 + y^2 = square root of -4?

Solar^
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Posts: n/a

 01-28-2006
I'm not sure if this is the forum for this but here goes:
In pre-calc were doing equations of circles, anyway have come up with
the equation for a circle that involves taking the square root of a
negative number to determine the radius. Don't know how to handle
this, thought some of you computer science/math guys might know.
Regards,
Solar^

Gordon
Guest
Posts: n/a

 01-28-2006
Solar^ wrote:
> I'm not sure if this is the forum for this but here goes:
> In pre-calc were doing equations of circles, anyway have come up with
> the equation for a circle that involves taking the square root of a
> negative number to determine the radius. Don't know how to handle
> this, thought some of you computer science/math guys might know.
> Regards,
> Solar^

isn't the square root of a negative number irrational or complex? (Been
a *very* long time since I did this - about 30 years!)

Geoff Pearson
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Posts: n/a

 01-28-2006

"Gordon" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed). uk...
> Solar^ wrote:
>> I'm not sure if this is the forum for this but here goes:
>> In pre-calc were doing equations of circles, anyway have come up with
>> the equation for a circle that involves taking the square root of a
>> negative number to determine the radius. Don't know how to handle
>> this, thought some of you computer science/math guys might know.
>> Regards,
>> Solar^

>
> isn't the square root of a negative number irrational or complex? (Been
> a *very* long time since I did this - about 30 years!)

yes squ rt of -4 is 2i where i= sq rt of -1 (whatever that is!)

Solar^
Guest
Posts: n/a

 01-28-2006
On Sat, 28 Jan 2006 18:39:19 +0000, Gordon
<(E-Mail Removed)> wrote:

>Solar^ wrote:
>> I'm not sure if this is the forum for this but here goes:
>> In pre-calc were doing equations of circles, anyway have come up with
>> the equation for a circle that involves taking the square root of a
>> negative number to determine the radius. Don't know how to handle
>> this, thought some of you computer science/math guys might know.
>> Regards,
>> Solar^

>
>isn't the square root of a negative number irrational or complex? (Been
>a *very* long time since I did this - about 30 years!)

Gordon,
Thanks for the reply. The resulting number would be imaginary or " i "
and I'm wondering if the radius of a circle can even be imaginary?
Regards,
Solar^

Budweiser
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Posts: n/a

 01-28-2006

"Solar^" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> I'm not sure if this is the forum for this but here goes:
> In pre-calc were doing equations of circles, anyway have come up with
> the equation for a circle that involves taking the square root of a
> negative number to determine the radius. Don't know how to handle
> this, thought some of you computer science/math guys might know.
> Regards,
> Solar^

Take a look here
http://www.mat.bham.ac.uk/maths_exte...es/complex.pdf

section 9 is probably what you are looking for,the rest you should be
able to class as revision.
Do not forget--all you are doing is resolving a triangle--albeit
constrained,be carefull to asses your calc to ensure you have the result
some other stuff
http://www.csun.edu/~ayk38384/math09...20Equation.htm

remember a circle can also be enclosed by a square,thus the radius can
be determined.

philo
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Posts: n/a

 01-28-2006
Solar^ wrote:
> I'm not sure if this is the forum for this but here goes:
> In pre-calc were doing equations of circles, anyway have come up with
> the equation for a circle that involves taking the square root of a
> negative number to determine the radius. Don't know how to handle
> this, thought some of you computer science/math guys might know.
> Regards,
> Solar^

imaginary numbers are often needed for calulating ...
\i recall a lot of it from when i was in engineering school...
some time in the previous century!

Mike Easter
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Posts: n/a

 01-28-2006
Solar^ wrote:
> I'm not sure if this is the forum for this but here goes:
> In pre-calc were doing equations of circles, anyway have come up with
> the equation for a circle that involves taking the square root of a
> negative number to determine the radius.

Is this a radius of an imaginary circle? As in one with a negative
area?

> Don't know how to handle
> this, thought some of you computer science/math guys might know.

I like wikipedia's discussion of imaginary numbers, especially because
they point out that all numbers are abstract anyway, including zero and
negative and fractional numbers in some contexts. Thus the abstract
imaginary numbers which represent i as the square root of -1 in the
complex number equation a + bi are as real and useful for their
functionality as are all of the rest of the number abstractions.

http://en.wikipedia.org/wiki/Imaginary_number Imaginary number
http://www.math.toronto.edu/mathnet/...imaginary.html Do "Imaginary
Numbers" Really Exist?

--
Mike Easter

Guest
Posts: n/a

 01-28-2006
On Sat, 28 Jan 2006 12:59:01 -0600, philo wrote:

> Solar^ wrote:
>> I'm not sure if this is the forum for this but here goes: In pre-calc
>> were doing equations of circles, anyway have come up with the equation
>> for a circle that involves taking the square root of a negative number
>> to determine the radius. Don't know how to handle this, thought some of
>> you computer science/math guys might know. Regards, Solar^

>
> imaginary numbers are often needed for calulating ... \i recall a lot of
> it from when i was in engineering school... some time in the previous
> century!

[flashback] My last term in engeneering was Spring 1966 at Michigan State.
Holy **** -- that's been 40 years now. They've probably discovered new
numbers that we didn't even know about back then. There's certainly lots
more for the physics and chem boys to know than there was back in those
days.

--
Killing all posts from Google Groups

Gordon
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Posts: n/a

 01-28-2006

>
> [flashback] My last term in engeneering was Spring 1966

Wow! You old git!

old jon
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 01-28-2006

"philo" <(E-Mail Removed)> wrote in message
news(E-Mail Removed). ..
> Solar^ wrote:
>> I'm not sure if this is the forum for this but here goes:
>> In pre-calc were doing equations of circles, anyway have come up with
>> the equation for a circle that involves taking the square root of a
>> negative number to determine the radius. Don't know how to handle
>> this, thought some of you computer science/math guys might know. Regards,
>> Solar^

>
>
> imaginary numbers are often needed for calulating ...
> \i recall a lot of it from when i was in engineering school...
> some time in the previous century!
>

That only makes you older than 6 philo <g>.