The Basel Problem / Zeta (2) and Wallis’s Product (VIDEO!)

In 1644, Italian mathematician Mengoli asked for the exact value of the infinite sum of the reciprocals of the square numbers: 1 + 1/4 + 1/9 + 1/16 + 1/25 + … = ?? He knew that the sum was bounded and wanted to know its value. Some ninety years later a young Leonhard Euler solved the problem and showed the exact answer to be (pi^2)/6. This is how Euler did it. (We’ll also derive Wallis’s product as a bonus!)



    QUADRATICS, Permutations and Combinations, EXPLODING DOTS, and more!

    Written for educators - and their students too! - this website, slowly growing, takes all the content Tanton has developed in his books, videos, and workshops, and organizes it into short, self-contained, and complete, curriculum units proving that mathematics, at all points of the school curriculum, can be joyous, fresh, innovative, rich, deep-thinking, and devoid of any rote doing! Let's teach generations of students to be self-reliant thinkers, willing to flail and to use their common sense to "nut their way" through challenges, to assess and judge results, and to adjust actions to find success. (Great life skills!)


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