Thank you VBBV.
Based on your reply, I wrote the following code:
syms w0 a b t m F0;
eqn = 2*b*w0*cos(w0*t) - 2*a*w0*sin(w0*t) == (F0*cos(w0*t))/m;
eq1 = subs(eqn, t, 0.5);
eq2 = subs(eqn, t, 0.6);
sys_eqn = [eq1 eq2];
sol = solve(sys_eqn, [a b])
sol = struct with fields:
a: 0
b: F0/(2*m*w0)