Baltic Way 1995 · Problem 17
Geometry
Prove that there exists a number such that for any triangle the inequality
holds, where denote the lengths of the altitudes and denote the lengths of the medians. Find the smallest possible value of .
When you’re ready
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Review
Topics
Geometric inequalities · Triangles and centers
Solutions
Solution
Solution:
Let and . If the longest height and the shortest median are drawn from the same vertex, then obviously .
Now let the longest height and shortest median be and , respectively, with and . Let be the point on the line such that is parallel to . Then , whence .
For an example with , consider a triangle where lies on the ray with . Hence the smallest such value is .
Contest context
Results from Baltic Way 1995
9 teams
- Mean score
- 2.0 / 5
- Scores of 4 or 5
- 3 / 9
- Estonia
- 0 / 5
Score distribution
All team scores
| Team | Score |
|---|---|
| Poland | 2 / 5 |
| Latvia | 0 / 5 |
| Sweden | 5 / 5 |
| Lithuania | 5 / 5 |
| Denmark | 5 / 5 |
| Finland | 0 / 5 |
| St. Petersburg | 0 / 5 |
| Estonia | 0 / 5 |
| Iceland | 1 / 5 |