AUTHOR=Abbass Ghulam , Katbar Nek Muhammad , Memon Israr Ahmed , Chen Haibo , Tesgera Tolasa Fikadu , Tolessa Lubo Gemeda TITLE=Numerical optimization of large-scale monotone equations using the free-derivative spectral conjugate gradient method JOURNAL=Frontiers in Applied Mathematics and Statistics VOLUME=11 YEAR=2025 URL=https://www.frontiersin.org/journals/applied-mathematics-and-statistics/articles/10.3389/fams.2025.1477774 DOI=10.3389/fams.2025.1477774 ISSN=2297-4687