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If veca, vecb and vecc are position vect...

If `veca, vecb` and `vecc` are position vectors of A,B, and C respectively of `DeltaABC` and `if|veca-vecb|=4,|vecb-vec(c)|=2, |vecc-veca|=3`, then the distance between the centroid and incenter of `triangleABC` is

A

1

B

`1/2`

C

`1/3`

D

`2/3`

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To find the distance between the centroid and the incenter of triangle ABC given the position vectors of points A, B, and C, we can follow these steps: ### Step 1: Define the position vectors Let: - \(\vec{a}\) be the position vector of point A - \(\vec{b}\) be the position vector of point B - \(\vec{c}\) be the position vector of point C ### Step 2: Use the given distances We are given: - \(|\vec{a} - \vec{b}| = 4\) - \(|\vec{b} - \vec{c}| = 2\) - \(|\vec{c} - \vec{a}| = 3\) ### Step 3: Find the centroid (G) The centroid \(G\) of triangle ABC is given by the formula: \[ \vec{G} = \frac{\vec{a} + \vec{b} + \vec{c}}{3} \] ### Step 4: Find the incenter (I) The incenter \(I\) can be calculated using the formula: \[ \vec{I} = \frac{a \vec{a} + b \vec{b} + c \vec{c}}{a + b + c} \] where \(a\), \(b\), and \(c\) are the lengths of the sides opposite to vertices A, B, and C respectively. ### Step 5: Calculate the lengths of the sides From the given distances, we can assign: - Let \(a = |\vec{b} - \vec{c}| = 2\) - Let \(b = |\vec{c} - \vec{a}| = 3\) - Let \(c = |\vec{a} - \vec{b}| = 4\) ### Step 6: Substitute the values into the incenter formula Now substituting the values into the incenter formula: \[ \vec{I} = \frac{2\vec{a} + 3\vec{b} + 4\vec{c}}{2 + 3 + 4} = \frac{2\vec{a} + 3\vec{b} + 4\vec{c}}{9} \] ### Step 7: Calculate the distance \(|\vec{I} - \vec{G}|\) Now we need to find the distance between the centroid and incenter: \[ |\vec{I} - \vec{G}| = \left| \frac{2\vec{a} + 3\vec{b} + 4\vec{c}}{9} - \frac{\vec{a} + \vec{b} + \vec{c}}{3} \right| \] ### Step 8: Simplify the expression To simplify, we can express \(\frac{\vec{a} + \vec{b} + \vec{c}}{3}\) in terms of a common denominator: \[ |\vec{I} - \vec{G}| = \left| \frac{2\vec{a} + 3\vec{b} + 4\vec{c}}{9} - \frac{3(\vec{a} + \vec{b} + \vec{c})}{9} \right| \] \[ = \left| \frac{(2\vec{a} + 3\vec{b} + 4\vec{c}) - (3\vec{a} + 3\vec{b} + 3\vec{c})}{9} \right| \] \[ = \left| \frac{-\vec{a} + 0\vec{b} + \vec{c}}{9} \right| \] \[ = \frac{|\vec{c} - \vec{a}|}{9} \] ### Step 9: Substitute the known distance From the problem, we know \(|\vec{c} - \vec{a}| = 3\): \[ |\vec{I} - \vec{G}| = \frac{3}{9} = \frac{1}{3} \] ### Conclusion Thus, the distance between the centroid and the incenter of triangle ABC is: \[ \frac{1}{3} \]

To find the distance between the centroid and the incenter of triangle ABC given the position vectors of points A, B, and C, we can follow these steps: ### Step 1: Define the position vectors Let: - \(\vec{a}\) be the position vector of point A - \(\vec{b}\) be the position vector of point B - \(\vec{c}\) be the position vector of point C ...
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