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If \\[ A=\\left( \\begin{array}{ccc}
a & b \\\\
c & d \\end{array} \\right),\\]
Then, the determinant is given by \\[{ad-bc}\\]
\nand the inverse of A = \\[ \\frac{1}{ad-bc} \\left( \\begin{array}{ccc}
d & -b \\\\
-c & a \\end{array} \\right),\\]
\n
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What is the determinant of A=$\\var{matrixA}$?
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