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Combitation

Discrete Mathematics Level 5

$\begin{aligned} ^{ x }{ { P } }_{ 2 } & =& 42 \\ (x-n)! & =& 120 \\ ^{ x }{ { C } }_{ n+3 } & =& \ ? \end{aligned}$

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Excel in math and science

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by Abdulrahman El Shafei

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