Find exact solution for few angles

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Hi everybody,

I have a couple of equations and I need to find the values of three variables (δ, λ, and θ).
The equations are:

M[11] = -(sin(δ)*cos(λ)*sin(2*θ)+sin(2*δ)*sin(λ)*sin(θ)^2)*M[0];
M[12] = (sin(δ)*cos(λ)*cos(2θ)+(1/2)*sin(2*δ)*sin(λ)*sin(2θ))*M[0];
M[13] = -(cos(δ)*cos(λ)*cos(θ)+cos(2*δ)*sin(λ)*sin(θ))*M[0];
M[22] = (sin(δ)*cos(λ)*sin(2*θ)-sin(2*δ)*sin(λ)*cos(θ)^2)*M[0];
M[23] = -(cos(δ)*cos(λ)*sin(θ)-cos(2*δ)*sin(λ)*cos(θ))*M[0];
M[33] = sin(2*δ)*sin(λ)*M[0];

where :
M[0]= 19.817; M[11]= 32.6; M[12] = -1.3; M[13] = -7.2; M[22] = 2.2; M23 = -13.5; M[33] = -24.7;

Any help would be highly appreciated.
 
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The last one:

This is straightforward to show that there's no exist δ λ such that:

-24.7= sin(2*δ)*sin(λ)*19.817

(this can be true only if δ λ are complex)
 
I have to agree with drszdrsz; some of these equations will not have real solutions. In particular, the first and last do not have real solutions.

As for the other ones... do it numerically?
 
Thanks for the replay. I also tried to solve these equations and i found that the solution contained complex number, however, the solution suppose to be real number.
i do not know how i can processed further.
please i need some suggestions.
 
Complex numbers might reduce to real numbers if you properly transform your equations...
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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