Question

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How do I multiply the two x-coordinates of the vectors and the two y-coordinates of v1=(22,15) and v2=(-2,4)?

Answer 1

Are you trying to calculate a dot product or inner product of some sort?

Answer 2

v1 dot v2 = x1*x2 + y1*y2

Answer 3

so 16?

Answer 4

if you're after the dot product... yes

Answer 5

\(\bf <a, b> \cdot <c, d> \implies a\times c + b\times d\)

Answer 6

@tkhunny honestly I'm not really sure, it says write each product below and use the dot product to determine which of the following vector pairs are othogonal.

Answer 7

hmm, didn't we cover this before?

Answer 8

you got it, but showing your work would make sure you weren't just lucky :)

Answer 9

if the dot product is 0 then the vectors are orthogonal.

Answer 10

Do you know the definition of orthogonal?

Answer 11

nope, what is it/

Answer 12

lol

Answer 13

for example (1,0) and (0,1) are orthogonal? But why?

Answer 14

http://openstudy.com/study#/updates/51fac0dbe4b0259e2c33b2f5

Answer 15

@pgpilot326 just presented the definition, but intuitively, do you know what it is?

Answer 16

uhm when it equals zero?

Answer 17

For example, the y-axis itself it orthogonal to the x-axis, they are perpendicular to each other

Answer 18

Also, the angle between the vectors is 90 degrees. This comes from another way to write the dot product: \( |v1| |v2| cos \theta = v1*v2 \). If \(\theta\) is 90 degrees, then the dot product is zero.

Answer 19

I need one more answer though

Answer 20

nevermind I got it! Thanks everyone for your help!

Answer 21

np