Imagine a 8x8 cell board, but missing two cell at the opposite corners, a domino take up exactly two cell, how to fill the board with dominoes so that none overlap or hang off the edge?

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This is a well-known problem - it even has its own wikipedia article: Mutilated chessboard problem. Here you can find a few similar but more challenging problems for trominos. Problems like this are usually solved using some type of coloring argument, as explained in Theo's comment and the above links. |
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