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In a three-dimensionalcoordinate system, `P ,Q ,a n dR`are images of a point `A(a ,b ,c)`in the `x-y ,y-za n dz-x`planes,respectively. If `G`is the centroid of triangle `P Q R ,`then area of triangle `A O G`is (`O`is the origin)a. `0`b. `a^2+b^2+c^2`c. `2/3(a^2+b^2+c^2)`d. noneof theseA. `0`B. `a^(2)+b^(2)+c^(2)`C. `(2)/(3) (a^(2)+b^(2)+c^(2))`D. None of these |
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Answer» Correct Answer - A A(a,b,c) Points P, Q & R are `(a,b,-c), (-a,b,c)` & `(a,-b,c)` Respectively Controied of `DeltaPQRT` is `((a)/(3), (b)/(3), (c)/(3))G` `rArr A, O, G` are collinear `rArr` Area of `DeltaAOG = 0` |
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