f(R)f(R) Cosmological solutions with varying speed of light

We consider f(R)f(R) modified gravity theories for describing varying speed of light in a spatially flat FRW model, and find some exact solutions. Also we examine the dynamics of this model by dynamical system method assuming a ΛCDM background and we find some exact solutions by considering the character of critical points of the theory in both formalisms. The behaviour of the speed of light is obtained.