Solving symbolic trig equation in terms of theta, using "sol."

What does "sol.th1" means ? why there are two sets of th1?

syms th1 th2 px py 
eq1 = px == cos(th1+th2)+cos(th1)
eq2 = py == sin(th1+th2)+sin(th1)
sol = solve(eq1,eq2,th1,th2)
th1 = simplify(sol.th1)
th2 = simplify(sol.th2)

th1 =

2*atan((2*py + (- px^4 - 2*px^2*py^2 + 4*px^2 - py^4 + 4*py^2)^(1/2))/(px^2 + 2*px + py^2))

2*atan((2*py - (- px^4 - 2*px^2*py^2 + 4*px^2 - py^4 + 4*py^2)^(1/2))/(px^2 + 2*px + py^2))

th2 =

-2*atan((-(px^2 + py^2)*(px^2 + py^2 - 4))^(1/2)/(px^2 + py^2))

2*atan((-(px^2 + py^2)*(px^2 + py^2 - 4))^(1/2)/(px^2 + py^2))

Answer 1

[madhan ravi]

The solution is returned in a struct so to access it you need to use the dot. It has occurred that there are two solutions?