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105萬芳高中

填6.
\(\displaystyle \lim_{n\to \infty}\frac{(1^2+2^2+3^2+\ldots+n^2)(1^5+2^5+3^5+\ldots+n^5)}{(1^3+2^3+3^3+\ldots+n^3)(1^4+2^4+3^4+\ldots+n^4)}=\)?
[解答]
n-->無限大時  (1^5+2^5+......n^5)/n^5=x^5 從0到1的積分=1/6
故所求=[(1/3)(1/6)]/[(1/4)(1/5)]=10/9

111.2.14補充
\(a_n=(1^2+2^2+\ldots+n^2)(1^5+2^5+\ldots+n^5)\),
\(b_n=(1^3+2^3+\ldots+n^3)(1^4+2^4+\ldots+n^4)\)
則\(\displaystyle \lim_{n\to \infty}\frac{a_n}{b_n}=\)為何?
105台南二中,https://math.pro/db/viewthread.php?tid=2487&page=4#pid15689

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