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Math Help - Vectors - parallel?

  1. #1
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    Post Vectors - parallel?

    How can I tell if these two vectors are parallel?

    u = <3,5>
    v = <-2, 1>

    Thanks for any help!
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  2. #2
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    Quote Originally Posted by live_laugh_luv27 View Post
    How can I tell if these two vectors are parallel?

    u = <3,5>
    v = <-2, 1>

    Thanks for any help!
    Two vectors are parallel if and only if one is a multiple of the other.
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  3. #3
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    Two vectors are parallel if they are non-zero multiples of each other.
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  4. #4
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    Post

    Ok..how would I know if they are multiples of one another?
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  5. #5
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    u = <3,5>
    v = <-2, 1>

    if two vectors are parrallel, then:

    u= kv, where k is some constant.

    <3,5>= k<-2,1>

    for values of x:
    3= -2k

    k= -3/2

    for values of y:
    5= (1)k

    since k for x does not equal to k for y, the two vectors are not parrallel.

    note: you could also use a dot product to check this
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  6. #6
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    Post

    great, thanks for explaining!
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