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#1 2007-01-23 12:23:48
- PRADEEP KUMAR PARRE
- Member
- Registered: 2007-01-23
- Posts: 1
solution for this problem
Hi,
question: P.T cos20cos40sin80=1/8
please send me the solution for this problem as soon as possible.
with regards
pradeep kumar parre
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#2 2007-01-23 19:59:29
- RauLiTo
- Member
- From: Bahrain
- Registered: 2006-01-11
- Posts: 142
Re: solution for this problem
sorry ... you may wrote the question by mistake
because by checking it with the calculator you will see that cos20cos40sin80 ≠ 1 / 8 
ImPo$$!BLe = NoTH!nG
Go DowN DeeP iNTo aNyTHinG U WiLL FinD MaTHeMaTiCs ...
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#3 2007-01-24 13:02:52
- Stanley_Marsh
- Member
- Registered: 2006-12-13
- Posts: 345
Re: solution for this problem
tranform it into cos10cos20cos40=sin10cos10cos20cos40/sin10=sin20cos20cos40/2sin10=sin40cos40/4sin10=sin80/8sin10=(1/8)*(sin80/sin10)=1/8*cot10. LOL , obviously it's not equal to 1/8~
Numbers are the essence of the Universe
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