Find the angle between the vectors u = 4i - 4j and v= - 4i +4j+ k The angle between the vectors is (Round to the nearest hundredth.) radians Find the angle between the vectors u = √5i - 9j and v= √5i+j-3k The angle between the vectors is radians. (Do not round until the final answer. Then round to the nearest hundredth as needed.)