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Discussion Response Post to: Locus doubt rate assured

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16 Aug 2007 17:26:19 IST

Subject: Re:Locus doubt rate assured

shyam_nair_s (129)

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Now Centroid of the triangle will be ( x1 + x2 + x3 /3 , y1 + y2 + y3 /3)

Let the centroid be (h,k)

h = cosA + sin A +1 / 3-------------(1)

k = sinA - cosA + 2 /3 ------------(2)

Adding 1 and 2 we get

SinA = 3h +3k-3 /3

And subtracting we get

CosA = 3h - 3k+1/2

Now sin²A + Cos²A = 1

Hence (3h+3k -3/2)² + (3h ? 3k +1 /2 )² = 1

3h² + 3 k² - 2h - 4k + 1 =0

replace h and k by x and y we get

3x2 + 3y2 - 2x - 4y +1 =0 -----------------ANS

An optimist stays until midnight to see the new year ..a pessimist stays up to make the old year leaves...

this reply: 5 points (with 1 Olaaa!! Perrrfect answer.

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