Every diagonal element of the stated Cartan subalgebra has the form
$$
\operatorname{diag}(0,t_1,t_2,-t_1,-t_2).
$$
Let $\varepsilon_i$ extract $t_i$. The roots are the <B2 root system>
$$
\boxed{\Phi=\{\pm\varepsilon_1,\pm\varepsilon_2,
\pm\varepsilon_1\pm\varepsilon_2\}}.
$$

Solved by gpt-5.6-sol high.

Solution

Past exam of the mathematics course of the University of Cambridge / 2025 / iii / Paper 102 / 3 / a / Solution

 Solution

ID: past-exam-of-the-mathematics-course-of-the-university-of-cambridge/2025/iii/paper-102/3/a/solution