Hi everyone :)
I'm new with Mathematica. For my university project I need to solve a system of 2 trigonometric equations. On the paper that I follow, they advise to do a change of variable to have a system of polynomials equations, but without giving the result. So I decided to use Mathematica in order to find the answer. Unfortunately neither the Solve function nor the Reduce function are working (I tried to let run an entire day without any results). However there is (are) a solution(s) because the paper show geometrical results. I would be very grateful for any kind of help !
Here my Wolfram Notebook
For curious interested on why I want to solve this system here the link to the paper.
More details : The change of variable is ta = tan(a/2), tb = tan(b/2)
that give : cos(a) = (1-ta^2)/(1+ta^2), sin(a) = 2*ta/(1+ta^2)
and same with cos(b), sin(b)
. Moreover 0 <= a <= 2pi, 0 <= b <= 2pi, d > 0 , l > 0
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