Euler Mathematics and Physics mainly serves students in primary schools, junior high schools and senior high schools. At present, it covers the contents of the national multi-textbook version of five disciplines: mathematics, English, physics, chemistry and biology. It uses AI video to make interesting secondary animation teaching AIDS, and helps to absorb and apply what it has learned by combining learning with practice.
Two-dimensional animation teaching aid: rich and interesting animation plots, combined with the simple analysis knowledge points of life scenes, make knowledge interesting and easy to understand.
a 1+a2+¡¡a(n- 1)+an=n^2an
& gt& gta 1+a2+¡¡a(n- 1)=(n^2- 1)an
& gt& gt£¿ s(n- 1)=(n^2- 1)[sn-s(n- 1)]
& gt& gtsn/s(n- 1)=n^2/(n^2- 1)=n/(n+ 1)*n/(n- 1)
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