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general graph transformation Watch

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    need help in this question ( will upload question after a sec)
    as i am confused about part c
    y=-f(x)+4

    as there any rule which transformation should i do before and which do after
    if i do the transformation of +4 ( move up 4 units) and then do -(fx)
    it will give points
    -2,-4
    -1,-8
    0,-7 i try to show in the graph ( top corner)

    and if i do -f(x) first and then +4 it will give points
    -1,0
    0,1

    why ? what i am doing wrong?/
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    Name:  df.PNG
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    RDKGames
    Desmos
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    I would say do -f(x) first and then +4, but you should wait for a reply from RDKGames, Notnek or Zacken.
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    (Original post by Desmos)
    I would say do -f(x) first and then +4, but you should wait for a reply from RDKGames, Notnek or Zacken.
    You're correct

    @OP, if you do +4 first you go from f(x) to g(x) = f(x) + 4 then (-1) gives h(x) = -4 - f(x) which is a different thing
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    (Original post by Zacken)
    You're correct

    @OP, if you do +4 first you go from f(x) to g(x) = f(x) + 4 then (-1) gives h(x) = -4 - f(x) which is a different thing
    OP, this may confuse you, so I would recommend you don't read this.

    But does  -f(x)+4 = -(f(x)-4)?
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    (Original post by Desmos)
    OP, this may confuse you, so I would recommend you don't read this.

    But does  -f(x)+4 = -(f(x)-4)?
    Yes
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    (Original post by Zacken)
    You're correct

    @OP, if you do +4 first you go from f(x) to g(x) = f(x) + 4 then (-1) gives h(x) = -4 - f(x) which is a different thing
    1. Translation in x f(x+a)
    2. Stretch in x f(ax)
    3. Reflect in x -af(x)
    4. Reflect in y f(-ax)
    5. Stretch in y af(x)
    6. Translate in y f(x)+a







    Desmos



    is that order id fine???
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    (Original post by Zacken)
    You're correct

    @OP, if you do +4 first you go from f(x) to g(x) = f(x) + 4 then (-1) gives h(x) = -4 - f(x) which is a different thing
    Qer if Zacken's explanation confuses you, here's another way to look at it:

    let f(x) = y
    then -f(x) + 4 = -y + 4


    But if we did +4 first, this is what happens:

    y → y+4 → -(y + 4) = -y - 4 = -f(x) - 4: Not what we were looking for
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    (Original post by Qer)
    1. Translation in x f(x+a)
    2. Stretch in x f(ax)
    3. Reflect in x -af(x)
    4. Reflect in y f(-ax)
    5. Stretch in y af(x)
    6. Translate in y f(x)+a







    Desmos



    is that order id fine???
    The order of operations should suffice.
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    I x -a I means both x and a are positive

    so x+a =0
    then x=-a???Name:  q.PNG
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    (Original post by Qer)
    I x -a I means both x and a are positive
    No it doesn't

    so x+a =0
    No?
    Name:  q.PNG
Views: 25
Size:  17.6 KB
    |b| = 0 if and only if b=0. So |x-a| = 0 if and only if x-a = 0
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    (Original post by Qer)
    I x -a I means both x and a are positive

    so x+a =0
    then x=-a???Name:  q.PNG
Views: 25
Size:  17.6 KB
    |x-a| means that whatever is between the || now becomes non-negative.
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    (Original post by Desmos)
    |x-a| means that whatever is between the || now becomes non-negative.
    This is what I am saying
    Isn't it?
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    (Original post by Qer)
    This is what I am saying
    Isn't it?
    No. You are saying that x \geq 0 and a \geq 0 which is not what |x-a| means
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    did i need to know how to find value of a reciprocal function without using a calculator for c3?? because Edexcel book have questions to find values without using calculator

    like sec240??
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    (Original post by Qer)
    This is what I am saying
    Isn't it?
    It becomes non-negative because the sign of whatever's inside changes if it's negative. So |2-5|=3
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    (Original post by Qer)
    did i need to know how to find value of a reciprocal function without using a calculator for c3?? because Edexcel book have questions to find values without using calculator

    like sec240??
    No. How would they know whether you have used a calc or not if you are allowed to use a calc on the paper...?
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    (Original post by RDKGames)
    No. How would they know whether you have used a calc or not if you are allowed to use a calc on the paper...?
    Yeah....I spend more than 1 and half hour on these....lol😫😫
 
 
 
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