Explicit solution could not be found

i am students and i am learning matlab

but i got obstacle

please help me

this is my code

a=180;
b=220;
c=180;
syms pa;
syms be;
[pa,be]=solve('(cos(pa))^2+R1*(sin(pa))^2-(c/b)*((cos(be))^2+R1*(sin(be))^2)=0','(R1-1)*con(pa)*sin(pa)-a/b*((cos(be))^2+R1*(sin(be))^2)=0','(1+R1)*cos(pa)*sin(pa)+(1-R1)*cos(be)*sin(be)=0','pa','be');

(i'm sorry that equation make you feel dizzy.)

if i command this code

i get Explicit solution could not be found

what means of that message? how to solve it?

thank you very much for reading

Answer 1

[Walter Roberson]

1. If you have N equations in N variables, then asking to solve for fewer than N variables will almost always tell you that no solution could be found.
2. In your second expression you need to fix the con(pa) to cos(pa)
3. What are you going to do with the large number of solutions over the imaginaries?
4. What are you going to do about the fact that sub-solutions to this problem involve polynomials which to any fixed numeric precision evaluate as having imaginary roots, but in the infinite precision limit the roots are completely real?

Answer 2

[Friedrich]

Hi,

this can mean

1. It's to complex for beeing solved symbolically
2. Since you have 3 equations and 2 variables it can mean that no solution exists at all, e.g.

   [x,y] = solve('x+y = 4','2*x+2*y = 8','x+y = 0')