A Permutation Product Minimum

★ 7/10combinatorics Estimation AM-GM inequality

Problem

Let $a_1, a_2, \ldots, a_9$ be any permutation of $1, 2, \ldots, 9$ . Find the minimum value of

a_1a_2a_3 + a_4a_5a_6 + a_7a_8a_9.

Answer

Solution

Difficulty	7/10
Topics	combinatorics, Estimation, AM-GM, inequality

Whiteboard

Your sketch is saved only in this browser. To share it, export your drawing as an image (whiteboard menu → Export as → PNG), then upload that image in the comments below.

Discussion

Ask questions, share alternate solutions, and use LaTeX freely.

0 comments

No comments yet.