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Math Help - evaluate given vectors

  1. #1
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    evaluate given vectors

    Please can someone help with this? I've been having a lot of problems with this. And if you could explain it an not just give me the answer, I'm trying to actually learn how to do this. Thank you for any help you can provide.

    Evaluate the expression:

    v ⋅ w

    Given the vectors:

    r = <8, 8, -6>; v = <3, -8, -3>; w = <-4, -2, -6>
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  2. #2
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    Re: evaluate given vectors

    Quote Originally Posted by Itel View Post
    Please can someone help with this? I've been having a lot of problems with this. And if you could explain it an not just give me the answer, I'm trying to actually learn how to do this. Thank you for any help you can provide.
    Evaluate the expression:
    v ⋅ w
    Given the vectors:
    r = <8, 8, -6>; v = <3, -8, -3>; w = <-4, -2, -6>

    <a,b,c>\cdot<x,y,z>=ax+by+cz.
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  3. #3
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    Re: evaluate given vectors

    Would it be
    8*3
    8*-8
    -6*-3?
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    Re: evaluate given vectors

    Quote Originally Posted by Itel View Post
    Would it be
    8*3
    8*-8
    -6*-3?
    NO INDEED.

    Apply the rule that I posted.
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  5. #5
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    Re: evaluate given vectors

    Which is 24+-64+18=-22?
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    Re: evaluate given vectors

    Quote Originally Posted by Itel View Post
    Which is 24+-64+18=-22?
    Which is correct. The dot product gives a number.
    Because it is negative tells us that the angle between the vectors is obtuse.
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  7. #7
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    Re: evaluate given vectors

    So that's the answer? -22 and its obtuse?
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  8. #8
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    Re: evaluate given vectors

    are you taking an online course?
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    Re: evaluate given vectors

    No. I'm in college.
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  10. #10
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    Re: evaluate given vectors

    Quote Originally Posted by Itel View Post
    No. I'm in college.
    REALLY? What in the world is that college is using as a textbook?
    Please name both college and textbook, as well as the course name.

    I find all your posts unbelievable coming from a college student studying anything to do with vectors.
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  11. #11
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    Re: evaluate given vectors

    Evaluate the expression:

    v ⋅ w

    Given the vectors:

    r = <8, 8, -6>; v = <3, -8, -3>; w = <-4, -2, -6>
    {\color{red}v \cdot w} = (3)(-4) + (-8)(-2) + (-3)(-6) = -12 + 16 + 18 = 22

    vector r = <8,8,-6> has no affect on the dot product of vectors v and w
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  12. #12
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    Re: evaluate given vectors

    What you don't believe me? :P

    West Georgia Technical College
    Math 1131 (which is calculus)
    ISBN 978-1-133-22867-7 or 1-133-22867-4 (I don't which one is which)
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