If the lines 
and 
are coplanar, find the values of α.
We know that the lines 
are coplanar if
Here,
(α – 5)[(3 – α)(2 – α) – 2] = 0
(α – 5)(6 – 3α – 2α + α2 – 2) = 0
(α – 1)(α – 4)(α – 5) = 0
α = 1, 4, 5
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If the lines and are coplanar, find the values of α.
We know that the lines are coplanar if
Here,
(α – 5)[(3 – α)(2 – α) – 2] = 0
(α – 5)(6 – 3α – 2α + α2 – 2) = 0
(α – 1)(α – 4)(α – 5) = 0
α = 1, 4, 5