HMMT 二月 2008 · 代数 · 第 1 题
HMMT February 2008 — Algebra — Problem 1
题目详情
英文原题
- [ 3 ] Positive real numbers x, y satisfy the equations x + y = 1 and x + y = . Find xy .
√18
解析
英文解析
- [ 3 ] Positive real numbers x, y satisfy the equations x + y = 1 and x + y = . Find xy .
1 1 118
2 2 2 2 2 4 4
Answer: We have 2 x y = ( x + y ) − ( x + y ) = , so xy = .
6 18 6
√