2. 外语
  3. Marjorie Rice was an unlikely candidate for the role of mathematical innovator. She had no formal education in mathematics and s

Marjorie Rice was an unlikely candidate for the role of mathematical innovator. She had no formal education in mathematics and s

admin2013-10-11  77
问题     Marjorie Rice was an unlikely candidate for the role of mathematical innovator. She had no formal education in mathematics and save a single course required for graduation from high school in 1939. Nonetheless, in 1975 she took up a problem that professional mathematicians had twice left for dead, and showed how much life was in still.
    The roblem was tessellation, or a rectangle — and fitting it together with copies of itself so that a plane is covered without any gaps or overlap. A region this plane would look rather like jigsaw puzzle whose pieces are all identical. Rice worked primarily with polygons, which consist only of straight lines. More specifically, she worked with convex polygons, in which the line joining any tow points on the polygon lies entirely within the polygon itself or on one of its edges. (A five-pointed star, for example, does not qualify as a convex polygon.)
    By the time Rice took up tiling, its basic properties had been established. Obviously, any square can tile the plane, as many kitchen floors have demonstrated. Equilateral triangles are also a fairly clear-cut case. There is one other regular polygon (a polygon whose angles, and sides, are equal) that can tile the plane: hexagon. This fact was established by the ancient Greeks but had long before been exploited by honeybees in building their honeycombs.
    And what of irregular polygons? As it turns out, any triangle or quadrilateral, no matter how devoid of regularity, will tile the plane. On the other hand, no convex polygon with more than six sides can do so, and the three classes of convex polygon that can were uncovered by the end of the First World War. So the only real question left by the time Marjorie Rice began her work was which convex pentagons tile the plane.
In the third paragraph, the author mentions honeycombs because_____.
选项 A、they prove that only regular polygons can tile the plane
B、they are an example of hexagonal structures
C、Greek mathematicians studied them
D、Marjorie Rice raised bees
答案B
解析 细节题。第三段第四句提到“There is one other regular polygon…hat can tile the plane：thehexagon”，接着作者引用了蜜蜂的例子，说明利用六边形原理建造的蜂巢非常坚固，以此来证明六边形适用于“tile the plane”。
转载请注明原文地址:https://www.kaotiyun.com/show/inGK777K
0

专业英语四级

相关试题推荐
随机试题
最新回复(0)