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The point having position vectors 2hati+...

The point having position vectors `2hati+3hatj+4hatk,3hati+4hatj+2hatk and 4hati+2hatj+3hatk` are the vertices of

A

A. right angled triangle

B

B. isosceles triangle

C

C. equilateral triangle

D

D. collinear

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To determine the type of triangle formed by the points with position vectors \( \mathbf{A} = 2\hat{i} + 3\hat{j} + 4\hat{k} \), \( \mathbf{B} = 3\hat{i} + 4\hat{j} + 2\hat{k} \), and \( \mathbf{C} = 4\hat{i} + 2\hat{j} + 3\hat{k} \), we will calculate the vectors representing the sides of the triangle and their magnitudes. ### Step 1: Calculate the vectors representing the sides of the triangle 1. **Vector \( \mathbf{AB} \)**: \[ \mathbf{AB} = \mathbf{B} - \mathbf{A} = (3\hat{i} + 4\hat{j} + 2\hat{k}) - (2\hat{i} + 3\hat{j} + 4\hat{k}) \] \[ = (3 - 2)\hat{i} + (4 - 3)\hat{j} + (2 - 4)\hat{k} = 1\hat{i} + 1\hat{j} - 2\hat{k} \] 2. **Vector \( \mathbf{BC} \)**: \[ \mathbf{BC} = \mathbf{C} - \mathbf{B} = (4\hat{i} + 2\hat{j} + 3\hat{k}) - (3\hat{i} + 4\hat{j} + 2\hat{k}) \] \[ = (4 - 3)\hat{i} + (2 - 4)\hat{j} + (3 - 2)\hat{k} = 1\hat{i} - 2\hat{j} + 1\hat{k} \] 3. **Vector \( \mathbf{AC} \)**: \[ \mathbf{AC} = \mathbf{C} - \mathbf{A} = (4\hat{i} + 2\hat{j} + 3\hat{k}) - (2\hat{i} + 3\hat{j} + 4\hat{k}) \] \[ = (4 - 2)\hat{i} + (2 - 3)\hat{j} + (3 - 4)\hat{k} = 2\hat{i} - 1\hat{j} - 1\hat{k} \] ### Step 2: Calculate the magnitudes of the vectors 1. **Magnitude of \( \mathbf{AB} \)**: \[ |\mathbf{AB}| = \sqrt{(1)^2 + (1)^2 + (-2)^2} = \sqrt{1 + 1 + 4} = \sqrt{6} \] 2. **Magnitude of \( \mathbf{BC} \)**: \[ |\mathbf{BC}| = \sqrt{(1)^2 + (-2)^2 + (1)^2} = \sqrt{1 + 4 + 1} = \sqrt{6} \] 3. **Magnitude of \( \mathbf{AC} \)**: \[ |\mathbf{AC}| = \sqrt{(2)^2 + (-1)^2 + (-1)^2} = \sqrt{4 + 1 + 1} = \sqrt{6} \] ### Step 3: Determine the type of triangle Since all three sides have equal lengths: \[ |\mathbf{AB}| = |\mathbf{BC}| = |\mathbf{AC}| = \sqrt{6} \] This means that the triangle formed by the points \( A \), \( B \), and \( C \) is an **equilateral triangle**. ### Final Answer The points having position vectors \( 2\hat{i} + 3\hat{j} + 4\hat{k} \), \( 3\hat{i} + 4\hat{j} + 2\hat{k} \), and \( 4\hat{i} + 2\hat{j} + 3\hat{k} \) are the vertices of an **equilateral triangle**.

To determine the type of triangle formed by the points with position vectors \( \mathbf{A} = 2\hat{i} + 3\hat{j} + 4\hat{k} \), \( \mathbf{B} = 3\hat{i} + 4\hat{j} + 2\hat{k} \), and \( \mathbf{C} = 4\hat{i} + 2\hat{j} + 3\hat{k} \), we will calculate the vectors representing the sides of the triangle and their magnitudes. ### Step 1: Calculate the vectors representing the sides of the triangle 1. **Vector \( \mathbf{AB} \)**: \[ \mathbf{AB} = \mathbf{B} - \mathbf{A} = (3\hat{i} + 4\hat{j} + 2\hat{k}) - (2\hat{i} + 3\hat{j} + 4\hat{k}) \] ...
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ARIHANT MATHS ENGLISH-VECTOR ALGEBRA-Exercise (Single Option Correct Type Questions)
  1. The direction cosines of vector a=3hati+4hatj+5hatk in the direction o...

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  2. The direction cosines of the vector 3hati-4hatj+5hatk are

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  3. The point having position vectors 2hati+3hatj+4hatk,3hati+4hatj+2hatk ...

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  4. If the position vectors of the vertices A,B and C of a DeltaABC are 7h...

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  5. If a,b and c are the position vectors of the vertices A,B and C of the...

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  6. If a and b are position vector of two points A,B and C divides AB in r...

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  7. Find the position vector of the point which divides the join of the po...

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  8. If O is origin and C is the mid - point of A (2, -1) and B ( -4, 3) . ...

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  9. If the position vectors of the points A and B are hati+3hatj-hatk and ...

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  10. The position vectors of A and B are hati-hatj+2hatk and 3hati-hatj+3ha...

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  11. If the vector vecb is collinear with the vector vec a ( 2sqrt2,-1,4) a...

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  12. If vec a , vec b are the position vectors of the points (1,-1),(-2,m)...

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  13. The points with position vectors 10hati+3hatj,12hati-5hatj and ahati+1...

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  14. The vectors hati+2hatj+3hatk,lamdahati+4hatj+7hatk,-3hati-2hatj-5hatk ...

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  15. If the points a+b,a-b and a+kb be collinear, then k is equal to

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  16. If the position vectors of A,B,C and D are 2hati+hatj,hati-3hatj,3hat...

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  17. If the vectors 3hati+2hatj-hatk and 6hati-4xhatj+yhatk are parallel, t...

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  18. If a and b are two non collinear vectors; then every vector r coplanar...

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  19. Four non-zero vectors will always be

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  20. The vectors a,b and a+b are

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