Given the vectors u = (2, a. 2, 1) and v = (1,2,-1,-1), where a is a scalar, determine
• (a) the value of a2 which gives a length of √25
• (b) the value of a for which the vectors u and v are orthogonal. Note: you may or may not get different a values for parts (a) and (b). Also note that in (a) the square of a is being asked for.