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    Graph has the points (-1,-3) and (3,1)

    equation y=f(3-x) is the transformation applied. given that there is a (-x) does this mean that the function to be applied is f(-x) or is it f(x-a)?

    Is there an order to determine which function/operation would go first?
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    (Original post by apronedsamurai)
    Graph has the points (-1,-3) and (3,1)

    equation y=f(3-x) is the transformation applied. given that there is a (-x) does this mean that the function to be applied is f(-x) or is it f(x-a)?

    Is there an order to determine which function/operation would go first?
    I did not understand this

    it might be helpful if you post a photo of the question
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    The diagram shows part of the graph of a function with equation y=f(x).

    two points are given (-1,-3) and (3,1).

    Which of the following shows the graph with equation y=f(3-x)?

    A (-3,4) (1,0)
    B (-6,1) (-2,-3)
    c (-4,3) (0,-1)
    D (-1,1) (3, -3)
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    (Original post by apronedsamurai)
    The diagram shows part of the graph of a function with equation y=f(x).

    two points are given (-1,-3) and (3,1).

    Which of the following shows the graph with equation y=f(3-x)?

    A (-3,4) (1,0)
    B (-6,1) (-2,-3)
    c (-4,3) (0,-1)
    D (-1,1) (3, -3)
    translation left by 3, reflection in the y axis

    (or for mathematical perverts, reflection in the y axis first, translation right by 3)
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    Ok,

    (-1,-3) and (3,1).

    Translation left by 3, as "a" >0; subtract from X; giving me (-4,-3). and (0,1).

    Reflection in Y axis;= multiply x co-ordinates by -1. (4,-3), (0,-1).

    So with that working/logic, I specified the answer as C. However, the answer given is B.



    Edit; no that is wrong also, because (0,1) would STILL be (0,1).
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    (Original post by apronedsamurai)
    Ok,

    (-1,-3) and (3,1).

    Translation left by 3, as "a" >0; subtract from X; giving me (-4,-3). and (0,1).

    Reflection in Y axis;= multiply x co-ordinates by -1. (4,-3), (0,-1).

    So with that working/logic, I specified the answer as C. However, the answer given is B.



    Edit; no that is wrong also, because (0,1) would STILL be (0,1).
    the points are not there ...

    so there is a mistake/typo somewhere in all of this
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    Yes, did it again; and it IS B.

    (3,1) Reflection in y axis; so (-3,1). Subtract a; a=3 (-6,1).

    (-1,-3) Reflection in y axis; so (1,-3). Subtract a; a=3 (-2,-3).

    Reflection has to come first. Doing the y=f(x+a) first; gives you a x value of 0 for (3,1) a>0; ergo, subtract a from x.
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    (Original post by apronedsamurai)
    Yes, did it again; and it IS B.

    (3,1) Reflection in y axis; so (-3,1). Subtract a; a=3 (-6,1).

    (-1,-3) Reflection in y axis; so (1,-3). Subtract a; a=3 (-2,-3).

    Reflection has to come first. Doing the y=f(x+a) first; gives you a x value of 0 for (3,1) a>0; ergo, subtract a from x.
    well I strongly beg to differ on this

    take the point (-1,3)
    the line y=-3x satisfies it

    now replace x by 3-x
    y=-3(3-x)
    y=3x-9

    NONE of these points is on this line
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    Its about graphs of functions? perhaps that the discrepancy?

    Ok, Ive checked with a maths tutor online, it IS B. The method I used was entirely proper.

    All I needed to know.
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    (Original post by apronedsamurai)
    Its about graphs of functions? perhaps that the discrepancy?

    Ok, Ive checked with a maths tutor online, it IS B. The method I used was entirely proper.

    All I needed to know.
    .....
 
 
 
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