Theorem: IMOSL.IMO2012A5.QuasiPeriodic.imp_left (IMOSLLean4/IMO2012/A5/A5General/A5QuasiPeriodic.lean)

State before:
R : Type u_2
S : Type u_1
inst✝² : NonAssocRing R
inst✝¹ : NonAssocRing S
inst✝ : NoZeroDivisors S
f : R → S
hf : NontrivialGood f
c : R
h : QuasiPeriodic f c
h0 : ∀ (x : R), f (x + c) = f x * -f c
x : R
⊢ f (c + x) = -f c * f x
Tactic:
rw [add_comm, h0, map_commute hf h]
State after:
no goals