Finding unknown n th roots ?  TOPIC_SOLVED

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Finding unknown n th roots ?

Postby wp_913 on Mon May 16, 2011 12:13 am

HI

I'm having trouble finding a solution to a fractional exponent that has an unknown denominator


such as 0.20 = 28.6 x (1/2)^3/x

I can easily determine the solution when the numerator of the fractional exponent is the unknown, but I'm stumped as how to determine the unknown value for a fractional exponent's denominator?

Any references would be most helpful

Thanks in advance.
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Postby stapel_eliz on Mon May 16, 2011 10:49 am

wp_913 wrote:I'm having trouble finding a solution to a fractional exponent that has an unknown denominator

such as 0.20 = 28.6 x (1/2)^3/x

Is the first "x" a variable or a "times" sign? :wink:

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Re: Finding unknown n th roots ?  TOPIC_SOLVED

Postby wp_913 on Mon May 16, 2011 11:38 pm

Hi All,

Ok I found the answer to my question by having it right in front of me and not realizing it.

I just take the log of both sides of the equation, isolate the variable by division, which leaves me with 7.1584 = x/0.4191.Then I just solve for x.

It took me a while to realize that it does not matter if the fractional exponent has a variable in the numerator or denominator.

Hopefully this may help someone else.
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