simp at this
Q : Type u_2
K : Type u_1
inst✝¹ : AddGroup Q
inst✝ : AddGroup K
c : Q → Q → K
ccl : Cocycle c
q : Q
this : c q 0 + c q 0 = q +ᵥ 0 + c q 0
⊢ c q 0 = 0
Q : Type u_2
K : Type u_1
inst✝¹ : AddGroup Q
inst✝ : AddGroup K
c : Q → Q → K
ccl : Cocycle c
q : Q
this : c q 0 = q +ᵥ 0
⊢ c q 0 = 0