Finding roots of trigonometric equation

Hi everyone!

I try to find the roots of the trigonometric equation below between 0 and 2*pi, but I have a logaritmic expression as an answer.

(-log(root(z^4 - (5*z^3*exp(13i/25))/11 - (5*z*exp(13i/25))/11 + exp(26i/25), z, 1))*1i)

How can I find the roots of this equation in the that interval?

Thank you in advance.

syms theta
vr=cos(theta)-2.2*cos(2*theta-0.52);
roots=solve(vr,theta)

Answer 1

[madhan ravi]

Roots=solve(vr,theta,'maxDegree',4)

[madhan ravi]

vpa(Roots)

[skinny pete]

thank you.