Question

Given the vectors u=(-2,3) and v=(2,1), determine a vector w as 2(u-w)+4(v+w)=0

Answer 1

yeah

Answer 2

are you sure you copy the right problem? just make sure about what we should do

Answer 3

@Teuzer knock, knock

Answer 4

ok

Answer 5

let w (x,y ) so tell me what u-w =??

Answer 6

in this problem 0= zero vector

Answer 7

let it aside, not touch it yet

Answer 8

just answer me, u-w =...

Answer 9

don't know

Answer 10

my god, u -w = (-2 -x, 3 -y) . you really not know about that? are you kidding me?

Answer 11

ohh. I know this. but how can I discovery w ?

Answer 12

take steps, please.!! ok, so how about 2 (u - w) =?

Answer 13

I believe the final result is w=(2,5)

Answer 14

Is that right?

Answer 15

how do you get it? teach me back, please

Answer 16

@phi rescue, please

Answer 17

wel. 2(-2-x,3-y) + 4(2+y,1+y)
(-4-2x,6-2y)+(8+4y,4+4y)
(4+2x,10+2y)
x=4/2 and y= 10/2

Answer 18

the last part is wrong, it is 4 ( 2 +x , 1 +y ) not 4 (2 +y ,....) that's mistake,

Answer 19

you redo, that's the right set up , just fix that mistake . show me your work

Answer 20

ok

Answer 21

I just wrote it wrong. but the result is right

Answer 22

nope, re calculate

Answer 23

so wherer it's wrong? i don't see it.

Answer 24

first term for x: -4 -2x +8 +4x = 4 +2x = 0 ---> 2x = -4---> x =-2

Answer 25

see it?

Answer 26

Ohh yeah. just the signal.

Answer 27

thnks phi for reply my tag. :)

Answer 28

value of y is the same.
@Teuzer it not "just the signal" in linear, it's wrong.

Answer 29

I got, i meant my mistake was upon the signal.

Answer 30

***Given the vectors u=(-2,3) and v=(2,1), determine a vector w as 2(u-w)+4(v+w)=0


I would divide both sides by 2 to simplify
2(u-w)+4(v+w)=0

u - w + 2(v+w)=0
distribute the 2 to get
u - w +2v + 2w= 0
combine 2w-w to get w:
u + 2v + w = 0
add -u -2v to both sides
w = -u -2v

notice this is like ordinary algebra.

now replace u and v with their vector values.
combine like components.

Answer 31

hehehee.... that's why I tag him, thanks phi . Perfect performance.

Answer 32

You still have to find the vector w.

Answer 33

Good thinking.

Answer 34

@phi, the leftover is the Asker's responsibility. easiest way, i gave out, professional way, you gave out. that's it.

Answer 35

to finish this, what is
-u if u is (-2,3) ?
what is -2v if v is (2,1) ?

once you get those vectors add corresponding components.