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January 18, 2026, 04:48:20 am

Author Topic: Vector Questions Help  (Read 1526 times)  Share 

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BlueYoHo

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Vector Questions Help
« on: March 16, 2009, 10:12:33 pm »
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Ok tonight I decided to do vectors instead :P And of course, got stuck again:

A, B and C are points defined by position vectors , and respectively.
M is a point of line segment AB, such that |AM| = |AC|.

Find:
i) AM
ii) the position vector which represents N, the midpoint of CM.

And the last part is hence show AN CM, but If I had AN and CM I could easily do that...

Thanks in advance :)
2009 - VCE Enter: 96.05
2010 - Monash University: BCom/BMechatronicEng

TrueTears

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Re: Vector Questions Help
« Reply #1 on: March 16, 2009, 10:15:23 pm »
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I suggest you do this for i)



Now, find AB = OB - OA

then find AC = OC - OA

AM = k(OB - OA)

so |AM| = | AC| Find the magnitude of AM in terms of k and magnitude of AC. Then solve for k :)

then sub k back in AM = k(OB-OA) and find AM

for ii) after you get k and found AM you can find OM which is just OA + AM.

Now that you have OM ( the position vector of M) you can find CM which is OM - OC, then CN must be

to find ON just do OC + CN

If you are stuck still, free feel to ask and I shall post my working :)
« Last Edit: March 16, 2009, 10:19:38 pm by TrueTears »
PhD @ MIT (Economics).

Interested in asset pricing, econometrics, and social choice theory.

BlueYoHo

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Re: Vector Questions Help
« Reply #2 on: March 16, 2009, 10:20:49 pm »
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Omg I hate when I do that. DUH I should have easily seen that, I'm gonna go work on it now, lol thanks.
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2010 - Monash University: BCom/BMechatronicEng

TrueTears

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Re: Vector Questions Help
« Reply #3 on: March 16, 2009, 10:24:26 pm »
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Omg I hate when I do that. DUH I should have easily seen that, I'm gonna go work on it now, lol thanks.
Hehe, those questions get trivial after some good vectors grinding :)
PhD @ MIT (Economics).

Interested in asset pricing, econometrics, and social choice theory.