Find the angle between the line joining the points (3, – 4, – 2) and (12, 2, 0) and the plane 3x – y + z = 1.
As we know that the angle θ between the line and a plane a2x + b2y + c2z + d2 = 0 is given by
……(1)
Given that the line is passing through A(3, – 4, – 2) and (12, 2, 0)
∴ the direction ratios of line AB are
= (12 – 3, 2 – (– 4), 0 – (– 2))
= (12 – 3, 2 + 4, 0 + 2)
= (9, 6, 2)
So,
a1 = 9, b1 = 6 and c1 = 2 ……(2)
Given equation of plane is 3x – y + z = 1
So,
a2 = 3, b2 = – 1 and c2 = 1 ……(3)
∴
⇒
⇒
⇒ θ = sin – 1 ()
Therefore the required angle is sin – 1 ()