Problema: O Emídio rodou o cubo que se apresenta na figura um sexto de volta em torno de $[AB]$. Qual é a interseção do cubo inicial com o cubo rodado? (image1)


Conteúdo referenciado:
[image1]
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[image2]
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[image3]
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[image4]
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[image5]
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[image6]
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Opções:
A) (image2)
B) (image3)
C) (image4)
D) (image5)
E) (image6)

Resolução: Os vértices $A$ e $B$, após a rotação vão ficar exatamente na mesma posição, porque pertencem ao eixo da rotação. Assim, as hipóteses B), C) e E) não estão corretas. Ao rodar e cortar o cubo, as faces vão ficar triangulares e um dos vértices de cada triângulo vai ser o ponto $A$ ou o ponto $B$. Opção correta: A).

Resposta correta: A