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Topic: 3 equation of cosine law
Replies: 8   Last Post: Apr 2, 2013 6:34 PM

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 Torsten Posts: 1,717 Registered: 11/8/10
Re: 3 equation of cosine law
Posted: Mar 22, 2013 7:59 AM
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"DHAAH JOHARI" wrote in message <kihfp2\$dmt\$1@newscl01ah.mathworks.com>...
> please help me..
> anyone know how to solve this problem..
> I have 3 simultaneous equation based on the cosine law..
>
> x^2=y^2+233600-966.64*y*cos(z-65.56);
> x^2=y^2+155600-788.92*y*cos(z-59.53);
> x^2=y^2+97600-624.82*y*cos(z-50.19);
>
> i know the answer for x=444.46, y=149.25
> but when i do the the coding like this below, i didn't get the same answer..i got
> x=-449.15, y=-295.21 and z=61.28
>
> syms xyz
> solutions = solve('x^2 = y^2+233600-966.64*y*cos(z-65.56) ',' x^2 = y^2+155600-788.92*y*cos(z-59.53)','x^2 = y^2+97600-624.82*y*cos(z-50.19)')
> [solutions.x solutions.y solutions.z]

I think you want to use "cosd" instead of "cos" in your equations.

Best wishes
Torsten.

Date Subject Author
3/22/13 Torsten
3/25/13 Torsten
3/28/13 Torsten
3/28/13 Roger Stafford
4/2/13 Guest
4/2/13 Roger Stafford

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