RECTANGULAR PARALLELEPIPED CHANGING INTO REGULAR N-POLYGON PRISM

摘要

PROBLEM TO BE SOLVED: To solve the problems that it is considerably difficult to realize the dimension of a regular n-polygon and it is not easy to obtain the dimension of one angle although the area of the regular n-polygon is the same as the area of n isosceles triangles, and most of conventional methods rely upon explanations by means of a diagram on a plane for understanding the nature of the regular n-polygon inscribed in a circle, and to allow the nature, the area, and the dimension of the regular n-polygon by using a gismo.;SOLUTION: In the gismo, 2n rectangular triangular prisms capable of deforming from a rectangular parallelepiped to a regular n-polygon prism are connected with each other. Accordingly, when obtaining the area of the regular n-polygon, it is easy to realize that the area of a rectangle at the side surface of the rectangular parallelepiped is equal to the area of the regular n-polygon at the bottom surface of the regular n-polygon prism after the change, and the area of the regular n-polygon is easily obtained by using this. Further, for example, the dimension of one angle on the regular n-polygon is easily obtained by only displaying the dimension of the rest angles other than the rectangle of the rectangular triangle. The gismo is capable of playing a sufficient role in understanding the nature of the regular n-polygon.;COPYRIGHT: (C)2011,JPO&INPIT