Theorem: ℤα.my_add_zero (Mordell4/Rt7Ring.lean)

State before:
a b c : ℤα
⊢ add a zero = a
Tactic:
cases' a with x y
State after:
case mk
b c : ℤα
x y : ℤ
⊢ add { z := x, w := y } zero = { z := x, w := y }

State before:
case mk
b c : ℤα
x y : ℤ
⊢ add { z := x, w := y } zero = { z := x, w := y }
Tactic:
simp only [add, zero, add_zero]
State after:
no goals