If the distance between the points `P(a ,2,1)a n d\ Q(1,-1,1)` is 5 units find the value of `adot`

Explanation

Given that: distance between the points `P(a, 2, 1) and Q(1, -1, 1) `is 5 units.


Formula used: The distance between any two points (a, b, c) and `(m, n, o)` is given by,


`sqrt[( a − m )^2 + ( b − n )^2 + ( c − o )^2 ]`


`PQ = 5 units `.


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