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**kevi555****Member**- Registered: 2005-11-29
- Posts: 1

Hi...

For this question you have to prove it by using vector methods.

Q: Prove that medians AD and BE of triangle ABC intersect at a point that divides each median in the ratio 2:1.

Any help would be greatly appreciated.

Thanks

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**tz****Guest**

OD = 1/2OB + 1/2OC

Let CF be the other median.

Prove that AD and BE's intersection, G divides AD in the ratio of 2:1.

Proof:

OD = 1/2OB + 1/2OC

OF = 1/2OA + 1/2OB

OD - OF = 1/2OC - 1/2OA

OD + 1/2OA = OF + 1/2OC

2OD + OA = 2OD + OC

2/3OD + 1/3OA = 2/3OF + 1/3OC

OG = OG

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