Net of a third of a cube in an A4 sheet
We fold an A4 sheet in four, we mark the small (green) side vertically from the middle to compose the base square. When unfolding, a rectangle will provide two large right triangles (the inner long diagonal of the cube), the two other squares, cut in half, will make two isosceles right triangles (the outer vertical half faces in the cube).
Quelles sont les dimensions de ces faces?