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#1 2009-11-16 03:11:23

sharanbr
Member
Registered: 2009-11-16
Posts: 1

cosine values

Hi Friends,

For my work, I need to calculate fixed values of cos/sine function.
Can you tell me the right approach:

1) Do I use a lookup available somewhere
2) Is there a formula/shortcut that will help me in this

For example, currently I am looking for values for:
* m1 = cos(4pi/16)
* m2 = cos(6pi/16)
* m3 = cos(2pi/16) - cos(6pi/16)
* m4 = cos(2pi/16)+ cos(6pi/16))

Regards,

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#2 2009-11-16 05:49:07

simplyjasper
Member
Registered: 2009-11-15
Posts: 24

Re: cosine values

Firstly approaching such question u should have some basic knowledge such as


There are many ways of solving these questions but I guess this formula would solve any angles

For example:



Another method:
Of course there's other ways such as drawing a right-angle isosceles triangle (that is 2 angles at 45 degrees and 1 angle at 90 degrees)
- the length and breadth would be at 1 unit and the hypotenuse is

by Pythagoras Theorem

A picture can be seen in the website below:
http://www.themathpage.com/aTrig/isosceles-right-triangle.htm


Last edited by simplyjasper (2009-11-16 05:53:55)

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