Mardianto, L., Mustika, M., Arfi, E., Kristian, R. D., Aisyah, N. N., & Riyantoko , P. A. (2026). Portfolio Optimization across Various Types of Variance-Covariance Matrices Using The Sequential Quadratic Programming (SQP) . Vygotsky: Jurnal Pendidikan Matematika Dan Matematika, 8(2), 177–188. https://doi.org/10.30736/voj.v8i2.1427