Question

Two vector A=(3, 4, -5) and B=(-1, 1, 2). Determine the magnitude of A+B and the direction (angle) of A+B ?

Answer 1

HI!!

Answer 2

did you find \(A+B\)?

Answer 3

Yes, it is \[\sqrt{38}\] and the angle I found is 121 but the answer it the book says it is 71 =(

Answer 4

oh
how did you find the angle (i actually am not sure what angle means in three dimensions)

Answer 5

A.B( dot product) = \[\left| A \right|.\left| B \right|\] .cos

Answer 6

doesn't that find the angle between the two vectors?

Answer 7

Yes, think the book has the wrong answer! thank you anyway ^^