A Variable Step-Size Exponentially Fitted Explicit Hybrid Method for Solving Oscillatory Problems

An exponentially fitted explicit hybrid method for solving oscillatory problems is obtained. This method has four stages. The first three stages of the method integrate exactly differential systems whose solutions can be expressed as linear combinations of {1, x, exp μx , exp −μx }, μ ∈ C, while the last stage of this method integrates exactly systems whose solutions are linear combinations of {1, x, x2, x3, x4, exp μx , exp −μx }. This method is implemented in variable step-size code basing on an embedding approach. The stability analysis is given. Numerical experiments that have been carried out show the efficiency of our method.