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#1 2006-12-26 11:07:51

unique
Member
Registered: 2006-10-04
Posts: 419

endpoints

find the length of the line segment with  endpoints (-4,0) and (5,4)

Desi
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#2 2006-12-26 11:41:50

luca-deltodesco
Member
Registered: 2006-05-05
Posts: 1,470

Re: endpoints

the length of the line segment defined by two end points is found by the differences in coordinates

(5,4) - (-4,0) = (9,4)  ,  sqrt( 9^2 + 4^2) = sqrt(97) = 9.85....

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#3 2006-12-26 12:12:43

LQ
Real Member
Registered: 2006-12-04
Posts: 1,285

Re: endpoints

I've heard that gravity has that value in some places. What memories.

I see clearly now, the universe have the black dots, Thus I am on my way of inventing this remedy...

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#4 2006-12-27 04:07:43

mathsyperson
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Registered: 2005-06-22
Posts: 4,900

Re: endpoints

If my calculations are right, then you'd need to be around 14km below sea level for gravity to be that high.

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It wanted to be normal.

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#5 2006-12-27 04:13:17

er.neerajsrivastava
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Registered: 2006-12-27
Posts: 9

Re: endpoints

help me please. what is the fastest way to compute 285714! (i.e. the factorial of 285714)?

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#6 2006-12-27 05:45:06

Devantè
Real Member
Registered: 2006-07-14
Posts: 6,400

Re: endpoints

Use this:

http://www.mathsisfun.com/forum/viewtopic.php?pid=54379#p54379

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#7 2006-12-27 07:53:17

krassi_holmz
Real Member
Registered: 2005-12-02
Posts: 1,905

Re: endpoints

mathsyperson wrote:

If my calculations are right, then you'd need to be around 14km below sea level for gravity to be that high.

What are these calculations?
And the gravity at poles is different than the gravity at the Equatior.

IPBLE:  Increasing Performance By Lowering Expectations.

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#8 2006-12-27 08:20:27

mathsyperson
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Registered: 2005-06-22
Posts: 4,900

Re: endpoints

I searched on Google to find the radius of the Earth and a precise value of g.

Then I used the g = Gm/r² thing to work out the mass of the earth, and then used that to work out at what distance from the centre the gravitional strength would be sqrt97. And then I just took that away from the standard radius to get the distance below sea level that it would have to be.

I didn't include all that in the post because it was off the point of the topic.

Why did the vector cross the road?
It wanted to be normal.

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#9 2006-12-27 08:50:37

krassi_holmz
Real Member
Registered: 2005-12-02
Posts: 1,905

Re: endpoints

Sorry for the off topic, but thank you for explainig me.
but... what's G? //sorry for the off-topic again

IPBLE:  Increasing Performance By Lowering Expectations.

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#10 2006-12-27 10:24:29

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

Re: endpoints

G is the gravitational constant (6.67 x 10^-11). The force due to gravity between two objects is given by:

Where m[sub]1[/sub] and m[sub]2[/sub] are the masses of the 2 objects, and r is the distance between them.

And don't worry about going off-topic, the original question has been resolved so it doesn't matter too much.

Why did the vector cross the road?
It wanted to be normal.

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#11 2006-12-27 12:13:31

krassi_holmz
Real Member
Registered: 2005-12-02
Posts: 1,905

Re: endpoints

Thank you again.
I'm asking, because in school we use 9.8 for g.

IPBLE:  Increasing Performance By Lowering Expectations.

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#12 2006-12-27 12:22:07

luca-deltodesco
Member
Registered: 2006-05-05
Posts: 1,470

Re: endpoints

G is the gravitational constant, it is universal. 9.8 rather, is the value of (G×mass of earth) / (average earth radius)^2

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