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Math Help - Definition of a plane using 3 points

  1. #1
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    Definition of a plane using 3 points

    n = (p2-p1) x (p3-p2)

    p1 =[0,1,1] p2 = [2,-1,2] p3 =[-3,1,0]

    = [ 2,-2,1] x [-5,2,-2]

    the answer is [2,-1,-6] but I can`t see how to get could someone show me please?
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  2. #2
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    Quote Originally Posted by aoibha View Post
    n = (p2-p1) x (p3-p2)
    p1 =[0,1,1] p2 = [2,-1,2] p3 =[-3,1,0]
    = [ 2,-2,1] x [-5,2,-2]
    the answer is [2,-1,-6] but I can`t see how to get could someone show me please?
    Frankly you notation is so poor as to make it impossible to follow.
    If we have points then


    Now take

    The plane is
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  3. #3
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    Is still dont see how to get [2,-1,-6]
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  4. #4
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    Quote Originally Posted by aoibha View Post
    Is still dont see how to get [2,-1,-6]
    Do you know how to do a cross product?
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  5. #5
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    Could you show me please?
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  6. #6
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    the direction of the cross product is determined by the right-hand rule. Here is the angle between the two vectors.
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