Using vector method, prove that the following points are collinear:
A(1,2,7) B(2,6,3) C(3,10,-1)

Explanation

We are given the points `A(1,2,7) quad B(2,6,3) quad C(3,10,-1)`


Let the position vectors be :


Position vector of ` A= hat i+2 hat j+7 hat k`


Position vector of ` B=2 hat i+6 hat j+3 hat k`


Position vector of `C=3 hat i+10 hat j - hat k`


Now we have to show that these points are collinear it is possible only if

`|vec(AB)|+|vec(BC)|=|vec(AC)|`


Therefore,


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