In this paper the problem of existence of solution of polynomial equations over the field of real numbers is considered. In particular, the explicit necessary and sufficient conditions are established for the equation A(z)X + B(z)Y = C(z) in polynomial matrices to have a solution for X and Y over the field of real numbers, with X being non-singular, for every polynomial matrix C(z) from a given class.
We give a full description of the dynamics of the Abel equation [formula] for some special complex valued ƒ. We also prove the existence of at least three periodic solutions for equations of the form [formula] for odd n ≥ 5.
We give a few sufficient conditions for the existence of periodic solutions of the equation [formula] where n > r and aj 's, ck's are complex valued. We prove the existence of one up to two periodic solutions.
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