1.Show that sin15∘ is irrational.[given that √3 is irrational and
sin15∘=(√6-√2)/4=√(2-√3)/2]
2.Show that if (2^m)+1 is a prime, where m≧2, is a integer, then m=2^n forsome positive integers n.
Pure math
2010-09-11 3:40 pm
回答 (1)
2010-09-11 5:08 pm
✔ 最佳答案
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2010-09-11 09:09:01 補充：
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原文連結 [永久失效]:
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