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Using properties of determinants prove that:

Solution:

\begin{array}{l} \left|\begin{array}{ccc} (\mathrm{x}-2)^{2} & (\mathrm{x}-1)^{2} & \mathrm{x}^{2} \\ (\mathrm{x}-1)^{2} & \mathrm{x}^{2} & (\mathrm{x}+1)^{2} \\ \mathrm{x}^{2} & (\mathrm{x}+1)^{2} & (\mathrm{x}+2)^{2} \end{array}\right| \\ =\left|\begin{array}{ccc} \mathrm{x}^{2}-4 \mathrm{x}+4 & \mathrm{x}^{2}-2 \mathrm{x}+1 & \mathrm{x}^{2} \\ \mathrm{x}^{2}-2 \mathrm{x}+1 & \mathrm{x}^{2} & \mathrm{x}^{2}+2 \mathrm{x}+1 \\ \mathrm{x}^{2} & \mathrm{x}^{2}+2 \mathrm{x}+1 & \mathrm{x}^{2}+4 \mathrm{x}+4 \end{array}\right| \\ =\left|\begin{array}{ccc} -2 \mathrm{x}+3 & -2 \mathrm{x}+1 & -2 \mathrm{x}-1 \\ -2 \mathrm{x}+1 & -2 \mathrm{x}-1 & -2 \mathrm{x}-3 \\ \mathrm{x}^{2} & \mathrm{x}^{2}+2 \mathrm{x}+1 & \mathrm{x}^{2}+4 \mathrm{x}+4 \end{array}\right|\left[\mathrm{R}_{1}^{\prime}=\mathrm{R}_{1}-\mathrm{R}_{2} \& \mathrm{R}_{2}^{\prime}=\mathrm{R}_{2}-\mathrm{R}_{3}\right] \end{array}


[transforming row and column]
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[expansion by first row]