kill(all)$

van=facebook.com/LearningCalculus$

f(x):=x^3+4*x-8$
g(x):=x^7+64*x^2$

s:solve(f(x),x)$

X:rhs(radcan(s[3]));

float(X);

g(X);

radcan(g(X));

van=facebook.com/LearningCalculus$

f(x):=x^3+4*cos(theta)*x-8*cos(theta)$
g(x):=x^7+(8*cos(theta))^2*x^2$

s:solve(f(x),x)$

f(x);

g(x);

X:radcan(rhs(s[3]));

g(X);