Question 739980
{{{(x^2yz)/((x-y)(x-z)) +(y^2zx)/((y-z)(y-x))+(z^2xy)/((z-x)(z-y))}}}
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This is not solving, just simplifying.
= {{{(x^2yz)/((x-y)(x-z)) -(y^2zx)/((y-z)(x-y))+(z^2xy)/((x-z)(y-z))}}}
Find a common denominator.  (x-y)(x-z)(y-z) works
= {{{(x^2yz)*(y-z)/DEN -(y^2zx)*(x-z)/DEN +(z^2xy)*(x-y)/DEN}}}
= {{{(xyz/DEN)*(x(y-z) - y(x-z) + z*(x-y))}}}
= {{{(xyz/DEN)*(xy - xz - xy + yz + xz - yz)}}}
= 0