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Challenging math problems inspired by ideas from around the world — original, adapted, and explained for curious students. Free to browse, no account needed.
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Featured Problems
See all →A Weighted Product Bound
Positive reals satisfy for . Define
P…
Two Zeros and a Power Bound
Let be a constant and
1. Discuss the monotonicity of . 2. Suppose has two zeros .
- Find the ran…
Conservative Sequences
A finite sequence with terms is called conservative if
Let be …
Chebyshev Coefficient Sum
Let with , and suppose for all . Find the maximum possible value of
A Piecewise Polynomial Ladder
A function on is defined piecewise: for (with ),
Determine, with proof, which o…
Reordering a Geometric Sequence
A finite geometric sequence has terms (), first term , and common ratio . Its terms are rearranged into a sequence suc…
Deeper Thinking
Problems designed to build mathematical insight, not just procedural skill.
Global Problem Craft
Original and adapted problems shaped by mathematical ideas from around the world.
Video Explanations
Many problems come with a companion YouTube video walking through the solution.