Module: Mathlib.Analysis.CStarAlgebra.ContinuousFunctionalCalculus.Pi

Goal state before:
pp: A : Type u_1
B : Type u_2
R : Type u_3
S : Type u_4
inst✝²⁸ : CommSemiring R
inst✝²⁷ : CommRing S
inst✝²⁶ : Nontrivial R
inst✝²⁵ : StarRing R
inst✝²⁴ : MetricSpace R
inst✝²³ : IsTopologicalSemiring R
inst✝²² : ContinuousStar R
inst✝²¹ : Algebra R S
inst✝²⁰ : NonUnitalRing A
inst✝¹⁹ : NonUnitalRing B
inst✝¹⁸ : Module S A
inst✝¹⁷ : Module R A
inst✝¹⁶ : Module R B
inst✝¹⁵ : Module S B
inst✝¹⁴ : SMulCommClass R A A
inst✝¹³ : SMulCommClass R B B
inst✝¹² : IsScalarTower R A A
inst✝¹¹ : IsScalarTower R B B
inst✝¹⁰ : StarRing A
inst✝⁹ : StarRing B
inst✝⁸ : TopologicalSpace A
inst✝⁷ : TopologicalSpace B
inst✝⁶ : IsScalarTower R S A
inst✝⁵ : IsScalarTower R S B
pab : A × B → Prop
pa : A → Prop
pb : B → Prop
inst✝⁴ : NonUnitalContinuousFunctionalCalculus R (A × B) pab
inst✝³ : NonUnitalContinuousFunctionalCalculus R A pa
inst✝² : NonUnitalContinuousFunctionalCalculus R B pb
inst✝¹ : ContinuousMapZero.UniqueHom R A
inst✝ : ContinuousMapZero.UniqueHom R B
f : R → R
a : A
b : B
hf : ContinuousOn f (quasispectrum R a ∪ quasispectrum R b)
hab : pab (a, b)
ha : pa a
hb : pb b
⊢ cfcₙ f (a, b) = (cfcₙ f a, cfcₙ f b)

Tactic:
by_cases hf₀ : f 0 = 0

Goal state after:
case pos
A : Type u_1
B : Type u_2
R : Type u_3
S : Type u_4
inst✝²⁸ : CommSemiring R
inst✝²⁷ : CommRing S
inst✝²⁶ : Nontrivial R
inst✝²⁵ : StarRing R
inst✝²⁴ : MetricSpace R
inst✝²³ : IsTopologicalSemiring R
inst✝²² : ContinuousStar R
inst✝²¹ : Algebra R S
inst✝²⁰ : NonUnitalRing A
inst✝¹⁹ : NonUnitalRing B
inst✝¹⁸ : Module S A
inst✝¹⁷ : Module R A
inst✝¹⁶ : Module R B
inst✝¹⁵ : Module S B
inst✝¹⁴ : SMulCommClass R A A
inst✝¹³ : SMulCommClass R B B
inst✝¹² : IsScalarTower R A A
inst✝¹¹ : IsScalarTower R B B
inst✝¹⁰ : StarRing A
inst✝⁹ : StarRing B
inst✝⁸ : TopologicalSpace A
inst✝⁷ : TopologicalSpace B
inst✝⁶ : IsScalarTower R S A
inst✝⁵ : IsScalarTower R S B
pab : A × B → Prop
pa : A → Prop
pb : B → Prop
inst✝⁴ : NonUnitalContinuousFunctionalCalculus R (A × B) pab
inst✝³ : NonUnitalContinuousFunctionalCalculus R A pa
inst✝² : NonUnitalContinuousFunctionalCalculus R B pb
inst✝¹ : ContinuousMapZero.UniqueHom R A
inst✝ : ContinuousMapZero.UniqueHom R B
f : R → R
a : A
b : B
hf : ContinuousOn f (quasispectrum R a ∪ quasispectrum R b)
hab : pab (a, b)
ha : pa a
hb : pb b
hf₀ : f 0 = 0
⊢ cfcₙ f (a, b) = (cfcₙ f a, cfcₙ f b)

case neg
A : Type u_1
B : Type u_2
R : Type u_3
S : Type u_4
inst✝²⁸ : CommSemiring R
inst✝²⁷ : CommRing S
inst✝²⁶ : Nontrivial R
inst✝²⁵ : StarRing R
inst✝²⁴ : MetricSpace R
inst✝²³ : IsTopologicalSemiring R
inst✝²² : ContinuousStar R
inst✝²¹ : Algebra R S
inst✝²⁰ : NonUnitalRing A
inst✝¹⁹ : NonUnitalRing B
inst✝¹⁸ : Module S A
inst✝¹⁷ : Module R A
inst✝¹⁶ : Module R B
inst✝¹⁵ : Module S B
inst✝¹⁴ : SMulCommClass R A A
inst✝¹³ : SMulCommClass R B B
inst✝¹² : IsScalarTower R A A
inst✝¹¹ : IsScalarTower R B B
inst✝¹⁰ : StarRing A
inst✝⁹ : StarRing B
inst✝⁸ : TopologicalSpace A
inst✝⁷ : TopologicalSpace B
inst✝⁶ : IsScalarTower R S A
inst✝⁵ : IsScalarTower R S B
pab : A × B → Prop
pa : A → Prop
pb : B → Prop
inst✝⁴ : NonUnitalContinuousFunctionalCalculus R (A × B) pab
inst✝³ : NonUnitalContinuousFunctionalCalculus R A pa
inst✝² : NonUnitalContinuousFunctionalCalculus R B pb
inst✝¹ : ContinuousMapZero.UniqueHom R A
inst✝ : ContinuousMapZero.UniqueHom R B
f : R → R
a : A
b : B
hf : ContinuousOn f (quasispectrum R a ∪ quasispectrum R b)
hab : pab (a, b)
ha : pa a
hb : pb b
hf₀ : ¬f 0 = 0
⊢ cfcₙ f (a, b) = (cfcₙ f a, cfcₙ f b)