Theorem: norm_cast_ne_two (FltRegular/NumberTheory/Cyclotomic/UnitLemmas.lean)

State before:
p : ℕ+
K : Type ?u.135468
inst✝² : Field K
ζ : K
hζ : IsPrimitiveRoot ζ ↑p
inst✝¹ : NumberField K
inst✝ : IsCyclotomicExtension {p} ℚ K
h : p ≠ 2
⊢ ↑p ≠ 2
Tactic:
contrapose! h
State after:
p : ℕ+
K : Type ?u.135468
inst✝² : Field K
ζ : K
hζ : IsPrimitiveRoot ζ ↑p
inst✝¹ : NumberField K
inst✝ : IsCyclotomicExtension {p} ℚ K
h : ↑p = 2
⊢ p = 2

State before:
p : ℕ+
K : Type ?u.135468
inst✝² : Field K
ζ : K
hζ : IsPrimitiveRoot ζ ↑p
inst✝¹ : NumberField K
inst✝ : IsCyclotomicExtension {p} ℚ K
h : ↑p = 2
⊢ p = 2
Tactic:
exact PNat.coe_injective h
State after:
no goals