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Homework Help: Translation and compression/expansion

  1. Feb 13, 2005 #1
    i have a question about translation and compression/expansion
    y=√x ; y=√2x-5

    how do u know u translate 5 units right first or horizontal compression by 1/2 first...?
  2. jcsd
  3. Feb 13, 2005 #2
    Y = 2(X^1/2) - 5

    if i got that correct
  4. Feb 13, 2005 #3


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    Is that [itex] y=\sqrt{2} x-5 [/itex] or [itex] y=\sqrt{2x}-5 [/itex]


  5. Feb 14, 2005 #4
    Exactly the same. There's no difference.
    If it involves f(nx+m), then you need to beware of it.
    If it involves nf(x)+m, no aware should be made.
    In this case, since not the first case, no aware.
  6. Feb 14, 2005 #5


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    If you simply replace x by x-5, the graph will be shifted 5 to the right.
    If you replace x by 2x, you will horizontally compress the graph by a factor 2.

    So, if you shift and then compress:
    [tex]\sqrt{x} \rightarrow \sqrt{x-5} \rightarrow \sqrt{2x-5}[/tex]

    and if you compress and then shift:
    [tex]\sqrt{x} \rightarrow \sqrt{2x} \rightarrow \sqrt{2(x-5)}[/tex]
  7. Feb 14, 2005 #6
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