Find the angle between the lines whose direction ratios are a, b, c and b – c, c – a, a – b.

Angle between the lines with direction ratios a1, b1, c1 and a2, b2, c2 is given by

Given -


a1 = a, b1 = b, c1 = c


a2 = b - c, b2 = c - a, c2 = a - b


So,


= 0


cosθ = 0


So, θ = 90°


Hence, Angle between the given pair of Lines is 90°.


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