Question 643938
x^-6 + y^-6
__________ 
x^-2 + y^-2 
The answer is: 
x^4 - x^2y^2 +y^4
_________________ 
x^4y^4 
I need to see the the steps on how to arive at this answer. 
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{{{(1/x^6+1/y^6)/(1/x^2-1/y^2)=((y^6+x^6)/(x^6y^6))/((y^2+x^2)/(x^2y^2))=(y^6+x^6)/(x^4y^4)(y^2+x^2)}}}
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{{{y^6+x^6=(y^2)^3+(x^2)^3=(y^2+x^2)(y^4-x^2y^2+x^4)= (sum of cubes)}}}
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{{{(y^6+x^6)/(x^4y^4)(y^2+x^2)=(y^2+x^2)(y^4-x^2y^2+x^4)/(x^4y^4)(y^2+x^2)=(y^4-x^2y^2+x^4)/(x^4y^4)=(x^4-x^2y^2+y^4)/(x^4y^4)}}}