SIGFIB - Editorial

May be noob question.
Can someone please explain the second decomposition in calculating E2?
i.e. how sigma(6x2yT[x,y,z]) = sigma((3x2y+6y2*x)*T[x,y,z])

May be noob question. Can someone please explain the second decomposition in calculating E2? i.e. how sigma(6x2yT[x,y,z]) = sigma((3x2y+6y2x)T[x,y,z])

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