Problem 1238 (difficulty: 3/10)

Find the maximum and minimum of \(\displaystyle xy\cdot\log(x^2+y^2)\) on \(\displaystyle x^2+y^2\le r\).

Give me another random problem!

Subject, section:
Requested difficulty:
Request for a concrete problem:I want problem no.

Supported by the Higher Education Restructuring Fund allocated to ELTE by the Hungarian Government