Challenging Problems in Geometry "I believe Ray Smullyan to

"I believe Ray Smullyan to be the Lewis Carroll of our times

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"Astonishing how this treatise … still retains a place of preeminence in modern acoustical literature

Challenging Problems in Geometry "I believe Ray Smullyan toDesigned for high school students and teachers with an interest in mathematical problem solving, this volume offers a wealth of nonroutine problems in geometry that stimulate students to explore unfamiliar or little known aspects of mathematics. Included are nearly 200 problems dealing with congruence and parallelism, the Pythagorean theorem, circles, area relationships, Ptolemy and the cyclic quadrilateral, collinearity and concurrency, and many