Sym_2(R) Jordan product: commutativity and Jordan identity literal-0 residuals

Exact symbolic verification on Sym_2(R), the 3-parameter space of 2×2 real symmetric matrices with Jordan product A∘B = (AB + BA)/2. Commutativity: A∘B − B∘A = (AB + BA)/2 − (BA + AB)/2 ≡ 0 — sympy returns the literal 2×2 zero matrix for…