→ bugmens :cos1度/(sin1度)^2 (出自1992 USAMO) 12/21 21:45
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 1.162.68.190
1 1 1
ex: ----------- + ----------- + ... + ------------- = ?
cos0'cos1' cos1'cos2' cos88'cos89'
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