formula

\[(y-z)x^{3}+(z-x)y^{3}+(x-y)z^{3}=-(x-y)(y-z)(z-x)(x+y+z)\]

'Beauty is truth, truth beauty,'-that is all Ye know on earth, and all ye need to know.
John Keats,"Ode on a Grecian Urn"





















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