Tedious Simplification: Show expression is real

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The discussion centers on a complex mathematical expression that the user believes should simplify to a real number, despite containing imaginary units. The user has attempted simplification using Maple and Mathematica but has not achieved significant results. They seek techniques or methods that could assist in further simplifying the expression. One suggestion involves manipulating the imaginary components, but the user finds it ineffective due to the complexity of the expression. Overall, the focus remains on finding a viable simplification method for the intricate expression presented.
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After doing A LOT of simplification on a complicated expression I am now at a point where my own skills can't take me any further.

My problem is that I have an expression, which I am almost certain must be real, but it contains the imaginary units here and there. I have tried using Maple and Mathematica with different assumptions, but it does not simplify very much.

Now, I do not expect you to do my tedious algebra. However, I was hoping that one of you might know of a technique (in Maple/Mathematica/Hand) that could help me?

My expression is this:

{\frac {\sqrt [3]{2}n \left( -1+n \right) \left( -1+2\,n \right) <br /> \left( 2\,\sqrt [3]{-2}+4\,\sqrt [3]{-2} \left( -1+n \right) n+<br /> \left( -1-2\,n \left( 1+ \left( -3+n \right) n \right) +i\sqrt {1-16<br /> \,n+44\,{n}^{2}-44\,{n}^{3}+28\,{n}^{4}-24\,{n}^{5}+12\,{n}^{6}}<br /> \right) ^{2/3}-i\sqrt {3} \left( -1-2\,n \left( 1+ \left( -3+n<br /> \right) n \right) +i\sqrt {1-16\,n+44\,{n}^{2}-44\,{n}^{3}+28\,{n}^{4<br /> }-24\,{n}^{5}+12\,{n}^{6}} \right) ^{2/3} \right) }{\sqrt [3]{-1-2\,n<br /> \left( 1+ \left( -3+n \right) n \right) +i\sqrt {1-16\,n+44\,{n}^{2}-<br /> 44\,{n}^{3}+28\,{n}^{4}-24\,{n}^{5}+12\,{n}^{6}}} \left( -8+16\,n<br /> \right) }}
where n is an interger larger than 1.

as you can see the same terms appear many places.Any help will be greatly appreciated.

Maple format:
Code:
2^(1/3)*n*(-1+n)*(-1+2*n)*(2*(-2)^(1/3)+4*(-2)^(1/3)*(-1+n)*n+(-1-2*n*(1+(-3+n)*n)+I*sqrt(1-16*n+44*n^2-44*n^3+28*n^4-24*n^5+12*n^6))^(2/3)-I*sqrt(3)*(-1-2*n*(1+(-3+n)*n)+I*sqrt(1-16*n+44*n^2-44*n^3+28*n^4-24*n^5+12*n^6))^(2/3))/((-1-2*n*(1+(-3+n)*n)+I*sqrt(1-16*n+44*n^2-44*n^3+28*n^4-24*n^5+12*n^6))^(1/3)*(-8+16*n))

Mathematica format:
Code:
(2^(1/3) (-1 + n) n (-1 + 2 n) (2 (-2)^(1/3) + 
     4 (-2)^(1/3) (-1 + n) n + (-1 - 2 n (1 + (-3 + n) n) + 
       I Sqrt[1 - 16 n + 44 n^2 - 44 n^3 + 28 n^4 - 24 n^5 + 
         12 n^6])^(2/3) - 
     I Sqrt[3] (-1 - 2 n (1 + (-3 + n) n) + 
        I Sqrt[1 - 16 n + 44 n^2 - 44 n^3 + 28 n^4 - 24 n^5 + 
          12 n^6])^(2/3)))/((-8 + 16 n) (-1 - 2 n (1 + (-3 + n) n) + 
     I Sqrt[1 - 16 n + 44 n^2 - 44 n^3 + 28 n^4 - 24 n^5 + 12 n^6])^(
   1/3))

Thanks in advance
 
Last edited:
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Here's one idea:

If the number is pure real, then you can multiply the i's by -1 and after this, you should have the same number as before.
 
Thanks. Yes, that is a good idea. However, the expression is so complicated that it doesn't really help. I can't show the expressions are the same.

And actually, which I should have clarified, I do need the simplified expression.
 
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