Determine whether the vectors u and v are parallel, orthogonal, or neither. u = , v = Orthogonal Neither Parallel

Question

Determine whether the vectors u and v are parallel, orthogonal, or neither. u = <3, 0>, v = <0, -6> Orthogonal Neither Parallel

unklerhaukus · Answer

what  do you get when you take the dot product?

unklerhaukus · Answer

the dot product of orthogonal vectors is always zero

anonymous · Answer

yes

anonymous · Answer

i got Neither

phi · Answer

do you know how to do a dot product ?

phi · Answer

multiply "corresponding" numbers  and add them up

anonymous · Answer

the dot product is given by :
u*v = u1v1 + u2v2

phi · Answer

what do you get ?

anonymous · Answer

sqrt(0^2 + -6^2) = 6i
sqrt(3^2 + 0^2) =3

phi · Answer

that looks like  you tried to find the length of each vector
(and by the way  -6*-6 is +36   so you get 6  not 6i )

but you want to do a dot product.  multiply the first # times the first # and 2nd # times the 2nd #  then add

anonymous · Answer

3*0 + 0*-6 =0

unklerhaukus · Answer

the magnitude (or lenght) is when you take the dot product of a vector with it self, which looks like what youve tied to do there,

but for this question you have to take the dot product of u with v

$$\vec u\cdot\vec v=\langle u_1,u_2\rangle\cdot\langle v_1,v_2\rangle=u_1v_1+u_2v_2$$.... like that

phi · Answer

yes,  and that is *very interesting*   0  means the vectors are orthogonal

unklerhaukus · Answer

yeah.

anonymous · Answer

lol ur name (UnkleRhaukus) i love boondocks

unklerhaukus · Answer

another way to do this problem would be to draw the vectors,

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