返回题库

HMMT 二月 2002 · 冲刺赛 · 第 8 题

HMMT February 2002 — Guts Round — Problem 8

专题
Contest Math / 竞赛数学
难度
L3
来源
HMMT

题目详情

英文原题

  1. [7] Draw a square of side length 1. Connect its sides’ midpoints to form a second square.
    Connect the midpoints of the sides of the second square to form a third square. Connect themidpoints of the sides of the third square to form a fourth square. And so forth. What isthe sum of the areas of all the squares in this infinite series?
解析

英文解析

  1. Draw a square of side length 1. Connect its sides’ midpoints to form a second square.
    Connect the midpoints of the sides of the second square to form a third square. Connect themidpoints of the sides of the third square to form a fourth square. And so forth. What isthe sum of the areas of all the squares in this infinite series?
    Solution: The area of the first square is 1, the area of the second is , the area of the 1
    1 1 1 12
    third is , etc., so the answer is 1 + + + + · · · = 2 .
    4 2 4 8