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Find the determinant of a random (2x2) matrix.
", "licence": "Creative Commons Attribution-NonCommercial 4.0 International"}, "statement": "Calculate the determinant of the following $2\\times2$ matrix.
", "advice": "In general, the determinant of a $2\\times2$ matrix is calculated as follows.
\n$$\\begin{vmatrix}A&B\\\\C&D\\end{vmatrix}=(A\\times D)-(B\\times C)$$
\nApplied to the question above,
\n$$\\begin{vmatrix}\\var{a1}&\\var{b1}\\\\\\var{a2}&\\var{b2}\\end{vmatrix}=(\\var{a1}\\times\\var{b2})-(\\var{b1}\\times\\var{a2})=\\var{a1*b2}-\\var{b1*a2}=\\var{det}$$
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