mathlib

65a5dc0f - feat(data/support): define support of a function and prove some properties (#2340)

feat(data/support): define support of a function and prove some properties (#2340) * feat(data/support): define support of a function and prove some properties * Add `support_mul'` for `group_with_zero` Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>