Question

Find the specified vector or scalar.

u = -4i + 1j and v = 4i + 1j; Find ‖u+v‖.
A. √34
B. 8
C. 2
D. 5

Answer 1

so what is u+v?

Answer 2

I have no clue

Answer 3

First do vector addition, so for the i's I would do -4+4=0, so 0i

Answer 4

when adding vector, you add the like components to get a new vector.

in your case, you have components pointing in the i direction and also in the j direction.

Answer 5

Now add the j s, what do you get?

Answer 6

so add the i components of the vectors to get a new i component.
add the j components to get a new j component.

Answer 7

ok i don't know how to do that can you help me solve

Answer 8

u = -4i + 1j
v = 4i + i j

u+v = (-4 + 4)i + (1 + 1)j = 0i + 2j

Answer 9

v = 4i + 1j sorry about the typo...

Answer 10

its ok :) so where would I go from there

Answer 11

so ||u + v|| is the magnitude (or length) of the vector. how long is the vector 0i+2j ? Can you draw it?

Answer 12

OK, i am with you i am trying to learn it

Answer 13

so the length of any vector can be found using the pythagorean theorem...