A Solution to Crux Mathematicorum Problem 4941
Crux Mathematicorum Problem 4941, followed by an incircle-inversion proof using the medial triangle of the contact triangle.
A study of form, relation, and proof
ELEMENTARY
GEOMETRYBeauty in Problems, Proofs, and Diagrams
A growing collection of Euclidean geometry: carefully stated problems, closely observed configurations, and precise proofs and diagrams. The emphasis is on seeing why a configuration works.
ENGLISHPROBLEMS · PROOFS · DIAGRAMS
Selected problem
A Solution to Crux Mathematicorum Problem 5021
Crux Mathematicorum Problem 5021, followed by a direct-similarity generalization proved with Pappus's theorem and a radical axis.
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More problems
Further problems and solutions
A Solution to Crux Mathematicorum Problem 5031
Crux Mathematicorum Problem 5031, followed by a concise incircle-inversion proof using contact-chord midpoints and a cyclic quadrilateral.
A Solution to Crux Mathematicorum Problem 5088
Crux Mathematicorum Problem 5088, followed by a concise angle-chasing proof through tangency and cyclic quadrilaterals.