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If \\[  A=\\left( \\begin{array}{ccc}
a & b  \\\\
c & d  \\end{array} \\right),\\]

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Then, the determinant is given by \\[{ad-bc}\\]

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and the inverse of A = \\[ \\frac{1}{ad-bc} \\left( \\begin{array}{ccc}
d & -b  \\\\
-c & a  \\end{array} \\right),\\]

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What is the determinant of A=$\\var{matrixA}$?

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What is the inverse of A=$\\var{matrixA}$?

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Determinant and inverse of a 2x2 matrix.

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