Syamsudhuha, S., Imran, M., Putri, A. and Marjulisa, R. 2026. A New Slope Averaging Technique in Heun’s Method: Combining Harmonic and Root Mean Square Means. Journal of the Indonesian Mathematical Society. 32, 3 (Sep. 2026), 1813. DOI:https://doi.org/10.22342/jims.v32i3.1813.