Given vectors u 37 and TeSolutiongiven u w uw 3 42 4
Given vectors u= (-3,7> and Te=
Solution
given u=<-3,7> , w=<1,-6>
u.w = <-3,7>.<1,-6> = - 3 - 42 = - 45
ll u ll = sqrt(9+49)= sqt(58) , ll v ll = sqrt(1+36) = sqt37
angle between vectors cos theta = u.w/llull llwll ]
= -45/[sqt58)sqt37]
=-0.971399
theta = arccos(-0.9714) =166.263
-> 2u = 2<-3,7> =<-6,14>
2u + w = <-6,14> + <1,-6> = <-5,8>
(2u+w).i = <-5,8>.i = - 5
