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Math Help - Dot or Cross product?

  1. #1
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    Dot or Cross product?

    If i need to find the angle between two vectors a, b, which method should i use? dot or cross product?

    And in when do i use dot/cross product to find the angle?
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  2. #2
    Moo
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    Hello,

    The dot product uses the cosine of the angle between the vectors and the cross product uses the sine of the angle
    So it depends/
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  3. #3
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    Quote Originally Posted by MilK View Post
    If i need to find the angle between two vectors a, b, which method should i use? dot or cross product?
    Well,given a choice, I'd prefer dot product. Computing it is simpler .
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  4. #4
    Moo
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    Quote Originally Posted by Isomorphism View Post
    Well,given a choice, I'd prefer dot product. Computing it is simpler .
    Plus, dot product can be used in 2D space, not cross product
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  5. #5
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    so if i want to find the angle, i can use either dot or cross product? which will give me the same result?
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  6. #6
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    Yes although I agree that using the dot product would in general be more easier. If you were given two vectors, would you rather find their scalar or cross product?
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  7. #7
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    of cos dot
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