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Homework Help: Inverse expressions

  1. Oct 15, 2006 #1
    yea ok but wait how do u find the inverse of like

    y=(x)^(1/3)

    y=3(2)^x

    whats the formula is not in the book

    BTW i can't do those equations in latex...
     
  2. jcsd
  3. Oct 15, 2006 #2
    interchange x and y, and solve for y.
     
  4. Oct 15, 2006 #3
    answer says y=x^3
     
  5. Oct 15, 2006 #4

    quasar987

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    which is exactly what courtrigrad's method predicts:

    1° interchange x and y: y=(x)^(1/3) --> x=y^(1/3)

    2° solve for y: x=y^(1/3) --> y=x^3
     
  6. Oct 15, 2006 #5
    make sure you understand algebra thomas, if you don't know all the algebra rules now, learn them b4 it's too late!
     
  7. Oct 15, 2006 #6

    HallsofIvy

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    For y= 3(2x), again do what courtrigrad said: Swap x and y to get x= 3(2y) and solve for y by taking logs of both sides:
    log(x)= log(3(2y))= ylog(2)+ log(3)
    y log(2)= log(x)- log(3)= log(x/3)
    y= log(x/3)/log(2).
     
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