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    The diagonals of the rectangle, AB and OC, meet at the point D.

    What information would i need to solve this question? Is it a simple: make AB=OC and solve? Cheers!
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    (Original post by lucy808)
    The diagonals of the rectangle, AB and OC, meet at the point D.

    What information would i need to solve this question? Is it a simple: make AB=OC and solve? Cheers!
    Err....well, what information do you have. Can you post the question?
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    7. The point A has position vector a = 2i + 2j + k and the point B has position vector b = i + j – 4k, relative to an origin O.

    (a)Find the position vector of the point C, with position vector c, given by c = a + b.

    (b) Show that OACB is a rectangle, and find its exact area.

    The diagonals of the rectangle, AB and OC, meet at the point D.

    (c) Write down the position vector of the point D.

    (d) Find the size of the angle ADC.

    (It's part C)
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    If OABC are the corners of your rectangle (going round in a clockwise fashion) then OB =OA-AB and then OD is OB/2.
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    Ichem you have the corners wrong. The rectangle is OACB

    OD is just 0.5(OC). Draw a diagram and you'll find these questions much more manageable.
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    (Original post by silent ninja)
    Ichem you have the corners wrong. The rectangle is OACB

    OD is just 0.5(OC). Draw a diagram and you'll find these questions much more manageable.
    Ah right, my bad!
 
 
 
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