rad(%theta):=%pi*%theta/180;

deg(%theta):=180*%theta/%pi;

Sin(%theta):=sin(rad(%theta));

Cos(%theta):=cos(rad(%theta));

n:4*Sin(20)*Sin(130)*Cos(130);

d:-Sin(20)+4*Sin(20)*Sin(130)^2-sqrt(3)*Cos(20);

x:atan(n/d);

float(deg(x));

radians(30);