SOLUTION: Please help me. {{{root(4,5x^8y^3/27x^2)}}}

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Question 212871: Please help me.
root%284%2C5x%5E8y%5E3%2F27x%5E2%29

Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
Please help me.
root%284%2C%285x%5E8y%5E3%29%2F%2827x%5E2%29%29

Subtract the exponents of the x's

root%284%2C5x%5E6y%5E3%2F27%29

Write the 27  as 3%2A3%2A3 and

root%284%2C%285x%5E6y%5E3%29%2F%283%2A3%2A3%29%29

Now take individual fourth roots of the
top and bottom.

root%284%2C%285x%5E6y%5E3%29%29%2Froot%284%2C%283%2A3%2A3%29%29%29


The denominator has only three factors of
3.  It needs one more 3, so it will be a 
perfect fourth power, and come out of the
fourth root radical.

So we multiply top and bottom of the fraction
by red%283%29.

root%284%2C%28+5x%5E6y%5E3%2Ared%283%29+%29%2F%283%2A3%2A3%2Ared%283%29%29%29

Now that there are 4 factors of 3 in the
denominator, we can write the denominator as
3%5E4 and simplify the numerator:

root%284%2C%2815x%5E6y%5E3+%29%2F%283%5E4%29%29 

Now we take individual fourth roots of the
top and bottom:

root%284%2C%2815x%5E6y%5E3+%29%29%2Froot%284%2C3%5E4%29%29

And since the bottom is the 4th root of
a 4th power we just take away the 4th root
radical and the 4th power.

root%284%2C%2815x%5E6y%5E3+%29%29%2F3

The factor x%5E6 is a case of an exponent 6
under a radical being as large or larger than, in
this case larger than, the index of the radical, 4.
That means it will simplify further.

So we write x%5E6 as red%28x%5E4x%5E2%29 so the x%5E4
will come out of the fourth root radical, like the 4
3's did above in the denominator.

root%284%2C%2815red%28x%5E4x%5E2%29y%5E3+%29%29%2F3

Now you can take x%5E4 out of the radical and
just have x in front of the radical on top:

x%2Aroot%284%2C%2815x%5E2y%5E3+%29%29%2F3  

Edwin