(2023) Question: The straight lines /, and 12 have respective vector equations:
(6) (3) (5) (7)
h = (1) + λ (4) I₂ = (8) + μ (1)
(0) (a) (b) (0)

where A and are scalar parameters while a and b are positive constants. Given that / and /2 intersect at some point P, forming an angle of 60°. Determine the value of a.