466 SOLUTIONS No problem is ever permanently closed. The editor ...
466 SOLUTIONS No problem is ever permanently closed. The editor ...
466 SOLUTIONS No problem is ever permanently closed. The editor ...
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¢¢¢ £<br />
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£¢¢ ¢£ P £¢ <br />
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u<br />
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£¢¢<br />
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p ′′ = u1v1(u2v3 + u3v2), u2v2(u1v3 + u3v1), u3v3(u1v2 + u2v1) <br />
£ £ <br />
−(u1v2 − u2v1) 2 ¢££ ¢<br />
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p = (v1v2, v2v3, v3v1)<br />
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£ <br />
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3<br />
√ 1/3 <br />
33 + 19 − 3 √ <br />
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33 + 1<br />
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≈ 1.84<br />
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£ ¢ 3 2 0 < r < 1<br />
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1/c = 1<br />
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3<br />
√ 1/3 <br />
33 + 17 − 3 √ <br />
1/3<br />
33 − 17 − 1 ≈ 0.54<br />
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2 n · 2 · 4 · 6 · · · (2n − 2) · n!<br />
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− 1<br />
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2 2n−1 n<br />
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n + 1 n<br />
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k=1<br />
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n<br />
k=1<br />
x 4<br />
k<br />
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≤ n3 (n 2 − 1)(3n 2 − 7)<br />
240<br />
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n<br />
k=1<br />
1<br />
k − 2 (n + 1) 4 xk<br />
xk<br />
4<br />
1<br />
k − 2 (n + 1) 2 n<br />
2 <br />
k=1<br />
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2 k<br />
2 1<br />
k − (n + 1)k + 4 (n + 1)2 2 <br />
n<br />
n<br />
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144<br />
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≤ n3 (n 2 − 1)(3n 2 − 7)<br />
240<br />
x 4<br />
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