Geometry doubt

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Re: Geometry doubt

by ankitns » Fri Aug 14, 2009 8:45 am
Could you please clarify further? Can you write out the whole question so we know what the context is?

Thanks.
winnerhere wrote:What does "the projection of one side on the other side in a triangle" mean?
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Re: Geometry doubt

by winnerhere » Fri Aug 14, 2009 8:54 am
Its a postulate which states

"In an acute angled triangle the square of the side opposite to the acute angle is less than the squares of the other two sides by a quantity equal to twice the product of one of these two sides and the projection of the second side on the first side"

With ABC an acute angled triangle

(AC)sq = (AB)sq + (BC)sq - 2 BC.BD

Thanks
ankitns wrote:Could you please clarify further? Can you write out the whole question so we know what the context is?

Thanks.
winnerhere wrote:What does "the projection of one side on the other side in a triangle" mean?