Find the acute angle between the line `bar(r).(hat(i) + 2hat(j) + 2hat(k)) + lambda (2hat(i) + 3hat(j) - 6hat(k))` and the plane `bar(r).(2hat(i) - hat(j) + hat(k)) = 0`.

Answer

`sin^(-1)((5)/(7sqrt(6)))`