By using the properties of determinants show that $(ii) \begin{vmatrix} x+y+2z&x&y \\ z&y+z+2x&y \\ z&x&z+x+2y \end{vmatrix} = 2(x+y+z)^3$

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Note: This is part 2 of a 2 part question, split as 2 separate questions here.