Solve For x

Discussion in 'Algebra' started by nycmathguy, Aug 29, 2021.

  1. nycmathguy

    nycmathguy

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    Solve for x.

    x^(x)^(5) = 100
     
    nycmathguy, Aug 29, 2021
    #1
  2. nycmathguy

    MathLover1

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    do you have [​IMG] or [​IMG]
     
    MathLover1, Aug 29, 2021
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  3. nycmathguy

    nycmathguy

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    It's x raised to the x raised to the 5. It's the first choice.
     
    nycmathguy, Aug 30, 2021
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  4. nycmathguy

    MathLover1

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    where did you find this problem? you did not find this in precalculus
     
    MathLover1, Aug 30, 2021
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  5. nycmathguy

    nycmathguy

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    I found this problem in a FB math group. There are so many FB math groups. I don't recall where this is posted. You can disregard the question if it is beyond precalculus. Take a look at the recently-posted word problems in the Basic Math forum.
     
    nycmathguy, Aug 30, 2021
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  6. nycmathguy

    MathLover1

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    this requires more knowledge beyond calculus III , advanced Calculus

    x^x^5 = 100......take log of both sides

    Rewrite the equation with
    2ln (10 )/5x=u
    and
    x= 2ln(10)/u5

    (2ln(10)/u5 )e^-u=1 ..........rewrite in Lambert form

    e^u*u=2ln(10)/5..........solve for u

    u=W[0](2ln(10)/5)...............substitute back u=2ln(10)/5x

    2ln(10)/5x=W[0](2ln(10)/5).........solve for x

    2ln(10)/W[0](2ln(10)/5)=5x

    x=2ln(10)/(W[0](2ln(10)/5)*5)

    x = 10^(1/5)->solution


    or, simplest way:
    Graph each side of the equation. The solution is the x-value of the point of intersection.
    x≈1.58489319
     
    MathLover1, Aug 30, 2021
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  7. nycmathguy

    nycmathguy

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    Wow! I saw the beginning video clip and quickly thought it was a simple algebra 2 problem. Considering what you said, this problem belongs in a different forum.
     
    nycmathguy, Aug 30, 2021
    #7
  8. nycmathguy

    nycmathguy

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    Here is the solution:

    20210901_203726.jpg
     
    nycmathguy, Sep 2, 2021
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  9. nycmathguy

    MathLover1

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    even simpler solution, I like it
    better than use Lambert form
     
    MathLover1, Sep 2, 2021
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  10. nycmathguy

    nycmathguy

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    Looks pretty easy to me.
     
    nycmathguy, Sep 2, 2021
    #10
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