Finding the minimum area of a triangle

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SUMMARY

The discussion focuses on finding the minimum area of a triangle formed by points A=(1,0,1) and B=(1,-1,0) with a third vertex on the line L:(x,y,z) = (t,t,t). The initial approach involves calculating vectors BA and BC and applying the area formula 1/2||BA x BC||. However, it is established that the area is minimized when the third point is closest to the line segment AB, which requires determining the distance between line L and segment AB. The concern regarding the cancellation of variable t in the calculations is clarified, confirming that it does not cancel out.

PREREQUISITES
  • Understanding of vector operations, specifically cross products
  • Familiarity with the area formula for triangles in three-dimensional space
  • Knowledge of distance calculations between a point and a line in 3D
  • Basic calculus concepts, particularly derivatives
NEXT STEPS
  • Study vector cross product applications in geometry
  • Learn about calculating distances from points to lines in three dimensions
  • Explore optimization techniques in calculus for minimizing functions
  • Investigate geometric interpretations of derivatives in multi-dimensional spaces
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Mathematicians, physics students, and anyone involved in computational geometry or optimization problems seeking to understand triangle area minimization in three-dimensional space.

Null_Pointer
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So i have the points A=(1,0,1) and B=(1,-1,0) and the third corner lies on the line
L:(x,y,z) = (t,t,t) and i need to find a triangle with the minimum area possible.

My initial approach was to calculate the vector BA and BC and then apply both vectors in the area triangle formula 1/2||BAxBC|| = area and then find a t that gives me the minimum area, but then I am wondering if this is correct since there may be a possibility that t can be canceled out and I'm left with a constant that comes from the derivate of the cross product.
 
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There is a simpler way, since A,B are fixed points, the area of the triangle is minimum if the third point is closest to AB. This is equivalent to find the distance between L and AB.
 
Null_Pointer said:
So i have the points A=(1,0,1) and B=(1,-1,0) and the third corner lies on the line
L:(x,y,z) = (t,t,t) and i need to find a triangle with the minimum area possible.

My initial approach was to calculate the vector BA and BC and then apply both vectors in the area triangle formula 1/2||BAxBC|| = area and then find a t that gives me the minimum area, but then I am wondering if this is correct since there may be a possibility that t can be canceled out and I'm left with a constant that comes from the derivate of the cross product.
Why would you worry about that possiblity? It doesn't cancel!
 

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