@ganeshie8
While solving for the shortest distance between two skew lines I came across a method
Distance=BA.Unit vector of PQ
Where BA is the vector obtained by subtracting starting point of a line with the other and Unit vector of PQ is the normal passing through both lines. How is the method correct?

If
r1 = a1+tb1, r2=a2+sb2
BA = a1-a2
PQ = b1 x b2/|b1 x b2| { x means cross product }

Question

@ganeshie8
While solving for the shortest distance between two skew lines I came across a method
Distance=BA.Unit vector of PQ
Where BA is the vector obtained by subtracting starting point of a line with the other and Unit vector of PQ is the normal passing through both lines. How is the method correct?

If
 r1 = a1+tb1, r2=a2+sb2
BA = a1-a2
PQ =  b1 x b2/|b1 x b2|      { x means cross product }

faiqraees · Answer

@Irishboy123

ganeshie8 · Answer

First consider a "point" and a "line" in 2D :

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faiqraees · Answer

Yes I know how to calculate in 2D. 
Dot product / magnitude of b  = a cos theta

ganeshie8 · Answer

Would you agree that the shortest distane between that point to the line is the perpendicular ?

faiqraees · Answer

Of course

ganeshie8 · Answer

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