Page 285 - HOW TO PROVE IT: A Structured Approach, Second Edition
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                                                     More Examples                     271























                                                        Figure 1
























                                                        Figure 2

                                                                               n
                                                                           n
                            Example 6.2.4. Prove that for any positive integer n,a2 × 2 square grid
                            with any one square removed can be covered with L-shaped tiles that look like:
                            this:

                            Scratch work
                                                                            n
                            Figure 3 shows an example for the case n = 2. In this case 2 = 4, so we have
                            a4 × 4 grid, and the square that has been removed is shaded. The heavy lines
                            show how the remaining squares can be covered with five L-shaped tiles.
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