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Bauglir
In pset1, part II, problem 2, part b), we're asked, "Given two non-zero vectors u and v, give the formula for the unit vector which bisects the (smaller) angle between u and v. (Use the notation uˆ for the unit vector in the u - direction.)" The solution given begins with, "Since u and v have the same length (=1)," which doesn't seem to be information given in the problem. In order to get there, wouldn't we first have to convert u and v to unit vectors?
It is a typo in the solution; It should be uˆ and vˆ everywhere.