Question

determine if the vectors u= 2i - 3j and v= 6i - 9j are parallel, orthogonal, or neither

Answer 1

if they are orthogonal the dot product between them has to be 0.

Answer 2

how did you get that?

Answer 3

wouldn't the dot product be 39 since (2*6)+(-3*-9)=39 right?

Answer 4

if not they are not orthogonal

Answer 5

i understand but are they parellel, orthogonal or neither? i thought it was neither but i got the question wrong

Answer 6

i mean that is a property, and works nice on this kind of problems

Answer 7

so by logig it was parellel according with the info you gave me

Answer 8

logic*

Answer 9

so what number range lets you know that it is parallel?

Answer 10

and that make sense cause the second one(v) is just 3U

Answer 11

if they are parallel one is just like the ohter one, only scaling by a factor of n

Answer 12

where n is a real number, (i guess you are only working with the real set)