NCERT Figure it Out 6 - Q1 - Exploring Some Geometric Themes
Question: In addition to the 5 ways shown in Fig. 4.8, are there any additional ways of gluing four cubes together along faces? Visualise and draw them (free tetrominoes / tetracubes).
Answer: Yes. Beyond the 5 flat tetrominoes there are additional non-planar tetracubes (8 free tetracubes in all).
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