By using properties of determinants,show that:
$\left|\begin{array}{ccc}1+a^{2}-b^{2} & 2 a b & -2 b \\ 2 a b & 1-a^{2}+b^{2} & 2 a \\ 2 b & -2 a & 1-a^{2}-b^{2}\end{array}\right|=\left(1+a^{2}+b^{2}\right)^{3}$

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(A) Let $\Delta = \left|\begin{array}{ccc}1+a^{2}-b^{2} & 2 a b & -2 b \\ 2 a b & 1-a^{2}+b^{2} & 2 a \\ 2 b & -2 a & 1-a^{2}-b^{2}\end{array}\right|$
Applying the row operations $R_{1} \rightarrow R_{1} + b R_{3}$ and $R_{2} \rightarrow R_{2} - a R_{3}$,we get:
$\Delta = \left|\begin{array}{ccc}1+a^{2}+b^{2} & 0 & -b(1+a^{2}+b^{2}) \\ 0 & 1+a^{2}+b^{2} & a(1+a^{2}+b^{2}) \\ 2 b & -2 a & 1-a^{2}-b^{2}\end{array}\right|$
Taking out common factors $(1+a^{2}+b^{2})$ from $R_{1}$ and $R_{2}$:
$\Delta = (1+a^{2}+b^{2})^{2} \left|\begin{array}{ccc}1 & 0 & -b \\ 0 & 1 & a \\ 2 b & -2 a & 1-a^{2}-b^{2}\end{array}\right|$
Expanding along $R_{1}$:
$\Delta = (1+a^{2}+b^{2})^{2} [1(1-a^{2}-b^{2} + 2a^{2}) - 0 + (-b)(0 - 2b)]$
$\Delta = (1+a^{2}+b^{2})^{2} [1+a^{2}-b^{2} + 2b^{2}]$
$\Delta = (1+a^{2}+b^{2})^{2} (1+a^{2}+b^{2}) = (1+a^{2}+b^{2})^{3}$

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