Theorems · Theorem · group theory

AddSubgroup.relIndex_map_map

∀ {G : Type u_1} {G' : Type u_2} [inst : AddGroup G] [inst_1 : AddGroup G'] (f : G →+ G') (H K : AddSubgroup G),
  (AddSubgroup.map f H).relIndex (AddSubgroup.map f K) = (H ⊔ f.ker).relIndex (K ⊔ f.ker)

Defined in

Mathlib.GroupTheory.Index

Cited by

1 results in Mathlib

Foundations

Depth 97 from the axioms · uses propext, Classical.choice, Quot.sound

Assumes

AddGroupAddGroup