Theorem madurid 21247

Description: Multiplying a matrix with its adjunct results in the identity matrix multiplied with the determinant of the matrix. See Proposition 4.16 in [Lang] p. 518. (Contributed by Stefan O'Rear, 16-Jul-2018.)

Hypotheses

Ref	Expression
madurid.a	⊢ 𝐴 = (𝑁 Mat 𝑅)
madurid.b	⊢ 𝐵 = (Base‘𝐴)
madurid.j	⊢ 𝐽 = (𝑁 maAdju 𝑅)
madurid.d	⊢ 𝐷 = (𝑁 maDet 𝑅)
madurid.i	⊢ 1 = (1r‘𝐴)
madurid.t	⊢ · = (.r‘𝐴)
madurid.s	⊢ ∙ = ( ·𝑠 ‘𝐴)

Assertion

Ref	Expression
madurid	⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → (𝑀 · (𝐽‘𝑀)) = ((𝐷‘𝑀) ∙ 1 ))

Proof of Theorem madurid

Dummy variables 𝑎 𝑏 𝑐 𝑑 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		eqid 2821	. . 3 ⊢ (𝑅 maMul ⟨𝑁, 𝑁, 𝑁⟩) = (𝑅 maMul ⟨𝑁, 𝑁, 𝑁⟩)
2		eqid 2821	. . 3 ⊢ (Base‘𝑅) = (Base‘𝑅)
3		eqid 2821	. . 3 ⊢ (.r‘𝑅) = (.r‘𝑅)
4		simpr 487	. . 3 ⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → 𝑅 ∈ CRing)
5		madurid.a	. . . . . 6 ⊢ 𝐴 = (𝑁 Mat 𝑅)
6		madurid.b	. . . . . 6 ⊢ 𝐵 = (Base‘𝐴)
7	5, 6	matrcl 21015	. . . . 5 ⊢ (𝑀 ∈ 𝐵 → (𝑁 ∈ Fin ∧ 𝑅 ∈ V))
8	7	simpld 497	. . . 4 ⊢ (𝑀 ∈ 𝐵 → 𝑁 ∈ Fin)
9	8	adantr 483	. . 3 ⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → 𝑁 ∈ Fin)
10	5, 2, 6	matbas2i 21025	. . . 4 ⊢ (𝑀 ∈ 𝐵 → 𝑀 ∈ ((Base‘𝑅) ↑m (𝑁 × 𝑁)))
11	10	adantr 483	. . 3 ⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → 𝑀 ∈ ((Base‘𝑅) ↑m (𝑁 × 𝑁)))
12		madurid.j	. . . . . . 7 ⊢ 𝐽 = (𝑁 maAdju 𝑅)
13	5, 12, 6	maduf 21244	. . . . . 6 ⊢ (𝑅 ∈ CRing → 𝐽:𝐵⟶𝐵)
14	13	adantl 484	. . . . 5 ⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → 𝐽:𝐵⟶𝐵)
15		simpl 485	. . . . 5 ⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → 𝑀 ∈ 𝐵)
16	14, 15	ffvelrnd 6847	. . . 4 ⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → (𝐽‘𝑀) ∈ 𝐵)
17	5, 2, 6	matbas2i 21025	. . . 4 ⊢ ((𝐽‘𝑀) ∈ 𝐵 → (𝐽‘𝑀) ∈ ((Base‘𝑅) ↑m (𝑁 × 𝑁)))
18	16, 17	syl 17	. . 3 ⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → (𝐽‘𝑀) ∈ ((Base‘𝑅) ↑m (𝑁 × 𝑁)))
19	1, 2, 3, 4, 9, 9, 9, 11, 18	mamuval 20991	. 2 ⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → (𝑀(𝑅 maMul ⟨𝑁, 𝑁, 𝑁⟩)(𝐽‘𝑀)) = (𝑎 ∈ 𝑁, 𝑏 ∈ 𝑁 ↦ (𝑅 Σg (𝑐 ∈ 𝑁 ↦ ((𝑎𝑀𝑐)(.r‘𝑅)(𝑐(𝐽‘𝑀)𝑏))))))
20	5, 1	matmulr 21041	. . . . 5 ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing) → (𝑅 maMul ⟨𝑁, 𝑁, 𝑁⟩) = (.r‘𝐴))
21	8, 20	sylan 582	. . . 4 ⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → (𝑅 maMul ⟨𝑁, 𝑁, 𝑁⟩) = (.r‘𝐴))
22		madurid.t	. . . 4 ⊢ · = (.r‘𝐴)
23	21, 22	syl6eqr 2874	. . 3 ⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → (𝑅 maMul ⟨𝑁, 𝑁, 𝑁⟩) = · )
24	23	oveqd 7167	. 2 ⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → (𝑀(𝑅 maMul ⟨𝑁, 𝑁, 𝑁⟩)(𝐽‘𝑀)) = (𝑀 · (𝐽‘𝑀)))
25		madurid.d	. . . . . 6 ⊢ 𝐷 = (𝑁 maDet 𝑅)
26		simp1l 1193	. . . . . 6 ⊢ (((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) → 𝑀 ∈ 𝐵)
27		simp1r 1194	. . . . . 6 ⊢ (((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) → 𝑅 ∈ CRing)
28		elmapi 8422	. . . . . . . . . 10 ⊢ (𝑀 ∈ ((Base‘𝑅) ↑m (𝑁 × 𝑁)) → 𝑀:(𝑁 × 𝑁)⟶(Base‘𝑅))
29	11, 28	syl 17	. . . . . . . . 9 ⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → 𝑀:(𝑁 × 𝑁)⟶(Base‘𝑅))
30	29	3ad2ant1 1129	. . . . . . . 8 ⊢ (((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) → 𝑀:(𝑁 × 𝑁)⟶(Base‘𝑅))
31	30	adantr 483	. . . . . . 7 ⊢ ((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ 𝑐 ∈ 𝑁) → 𝑀:(𝑁 × 𝑁)⟶(Base‘𝑅))
32		simpl2 1188	. . . . . . 7 ⊢ ((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ 𝑐 ∈ 𝑁) → 𝑎 ∈ 𝑁)
33		simpr 487	. . . . . . 7 ⊢ ((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ 𝑐 ∈ 𝑁) → 𝑐 ∈ 𝑁)
34	31, 32, 33	fovrnd 7314	. . . . . 6 ⊢ ((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ 𝑐 ∈ 𝑁) → (𝑎𝑀𝑐) ∈ (Base‘𝑅))
35		simp3 1134	. . . . . 6 ⊢ (((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) → 𝑏 ∈ 𝑁)
36	5, 12, 6, 25, 3, 2, 26, 27, 34, 35	madugsum 21246	. . . . 5 ⊢ (((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) → (𝑅 Σg (𝑐 ∈ 𝑁 ↦ ((𝑎𝑀𝑐)(.r‘𝑅)(𝑐(𝐽‘𝑀)𝑏)))) = (𝐷‘(𝑑 ∈ 𝑁, 𝑐 ∈ 𝑁 ↦ if(𝑑 = 𝑏, (𝑎𝑀𝑐), (𝑑𝑀𝑐)))))
37		iftrue 4473	. . . . . . . . 9 ⊢ (𝑎 = 𝑏 → if(𝑎 = 𝑏, (𝐷‘𝑀), (0g‘𝑅)) = (𝐷‘𝑀))
38	37	adantl 484	. . . . . . . 8 ⊢ (((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 = 𝑏) → if(𝑎 = 𝑏, (𝐷‘𝑀), (0g‘𝑅)) = (𝐷‘𝑀))
39	29	ffnd 6510	. . . . . . . . . . . 12 ⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → 𝑀 Fn (𝑁 × 𝑁))
40		fnov 7276	. . . . . . . . . . . 12 ⊢ (𝑀 Fn (𝑁 × 𝑁) ↔ 𝑀 = (𝑑 ∈ 𝑁, 𝑐 ∈ 𝑁 ↦ (𝑑𝑀𝑐)))
41	39, 40	sylib 220	. . . . . . . . . . 11 ⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → 𝑀 = (𝑑 ∈ 𝑁, 𝑐 ∈ 𝑁 ↦ (𝑑𝑀𝑐)))
42	41	adantr 483	. . . . . . . . . 10 ⊢ (((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 = 𝑏) → 𝑀 = (𝑑 ∈ 𝑁, 𝑐 ∈ 𝑁 ↦ (𝑑𝑀𝑐)))
43		equtr2 2030	. . . . . . . . . . . . . . 15 ⊢ ((𝑎 = 𝑏 ∧ 𝑑 = 𝑏) → 𝑎 = 𝑑)
44	43	oveq1d 7165	. . . . . . . . . . . . . 14 ⊢ ((𝑎 = 𝑏 ∧ 𝑑 = 𝑏) → (𝑎𝑀𝑐) = (𝑑𝑀𝑐))
45	44	ifeq1da 4497	. . . . . . . . . . . . 13 ⊢ (𝑎 = 𝑏 → if(𝑑 = 𝑏, (𝑎𝑀𝑐), (𝑑𝑀𝑐)) = if(𝑑 = 𝑏, (𝑑𝑀𝑐), (𝑑𝑀𝑐)))
46		ifid 4506	. . . . . . . . . . . . 13 ⊢ if(𝑑 = 𝑏, (𝑑𝑀𝑐), (𝑑𝑀𝑐)) = (𝑑𝑀𝑐)
47	45, 46	syl6eq 2872	. . . . . . . . . . . 12 ⊢ (𝑎 = 𝑏 → if(𝑑 = 𝑏, (𝑎𝑀𝑐), (𝑑𝑀𝑐)) = (𝑑𝑀𝑐))
48	47	adantl 484	. . . . . . . . . . 11 ⊢ (((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 = 𝑏) → if(𝑑 = 𝑏, (𝑎𝑀𝑐), (𝑑𝑀𝑐)) = (𝑑𝑀𝑐))
49	48	mpoeq3dv 7227	. . . . . . . . . 10 ⊢ (((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 = 𝑏) → (𝑑 ∈ 𝑁, 𝑐 ∈ 𝑁 ↦ if(𝑑 = 𝑏, (𝑎𝑀𝑐), (𝑑𝑀𝑐))) = (𝑑 ∈ 𝑁, 𝑐 ∈ 𝑁 ↦ (𝑑𝑀𝑐)))
50	42, 49	eqtr4d 2859	. . . . . . . . 9 ⊢ (((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 = 𝑏) → 𝑀 = (𝑑 ∈ 𝑁, 𝑐 ∈ 𝑁 ↦ if(𝑑 = 𝑏, (𝑎𝑀𝑐), (𝑑𝑀𝑐))))
51	50	fveq2d 6669	. . . . . . . 8 ⊢ (((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 = 𝑏) → (𝐷‘𝑀) = (𝐷‘(𝑑 ∈ 𝑁, 𝑐 ∈ 𝑁 ↦ if(𝑑 = 𝑏, (𝑎𝑀𝑐), (𝑑𝑀𝑐)))))
52	38, 51	eqtr2d 2857	. . . . . . 7 ⊢ (((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 = 𝑏) → (𝐷‘(𝑑 ∈ 𝑁, 𝑐 ∈ 𝑁 ↦ if(𝑑 = 𝑏, (𝑎𝑀𝑐), (𝑑𝑀𝑐)))) = if(𝑎 = 𝑏, (𝐷‘𝑀), (0g‘𝑅)))
53	52	3ad2antl1 1181	. . . . . 6 ⊢ ((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ 𝑎 = 𝑏) → (𝐷‘(𝑑 ∈ 𝑁, 𝑐 ∈ 𝑁 ↦ if(𝑑 = 𝑏, (𝑎𝑀𝑐), (𝑑𝑀𝑐)))) = if(𝑎 = 𝑏, (𝐷‘𝑀), (0g‘𝑅)))
54		eqid 2821	. . . . . . . 8 ⊢ (0g‘𝑅) = (0g‘𝑅)
55		simpl1r 1221	. . . . . . . 8 ⊢ ((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ ¬ 𝑎 = 𝑏) → 𝑅 ∈ CRing)
56	9	3ad2ant1 1129	. . . . . . . . 9 ⊢ (((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) → 𝑁 ∈ Fin)
57	56	adantr 483	. . . . . . . 8 ⊢ ((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ ¬ 𝑎 = 𝑏) → 𝑁 ∈ Fin)
58	30	ad2antrr 724	. . . . . . . . 9 ⊢ (((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ ¬ 𝑎 = 𝑏) ∧ 𝑐 ∈ 𝑁) → 𝑀:(𝑁 × 𝑁)⟶(Base‘𝑅))
59		simpll2 1209	. . . . . . . . 9 ⊢ (((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ ¬ 𝑎 = 𝑏) ∧ 𝑐 ∈ 𝑁) → 𝑎 ∈ 𝑁)
60		simpr 487	. . . . . . . . 9 ⊢ (((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ ¬ 𝑎 = 𝑏) ∧ 𝑐 ∈ 𝑁) → 𝑐 ∈ 𝑁)
61	58, 59, 60	fovrnd 7314	. . . . . . . 8 ⊢ (((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ ¬ 𝑎 = 𝑏) ∧ 𝑐 ∈ 𝑁) → (𝑎𝑀𝑐) ∈ (Base‘𝑅))
62	30	adantr 483	. . . . . . . . . 10 ⊢ ((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ ¬ 𝑎 = 𝑏) → 𝑀:(𝑁 × 𝑁)⟶(Base‘𝑅))
63	62	fovrnda 7313	. . . . . . . . 9 ⊢ (((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ ¬ 𝑎 = 𝑏) ∧ (𝑑 ∈ 𝑁 ∧ 𝑐 ∈ 𝑁)) → (𝑑𝑀𝑐) ∈ (Base‘𝑅))
64	63	3impb 1111	. . . . . . . 8 ⊢ (((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ ¬ 𝑎 = 𝑏) ∧ 𝑑 ∈ 𝑁 ∧ 𝑐 ∈ 𝑁) → (𝑑𝑀𝑐) ∈ (Base‘𝑅))
65		simpl3 1189	. . . . . . . 8 ⊢ ((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ ¬ 𝑎 = 𝑏) → 𝑏 ∈ 𝑁)
66		simpl2 1188	. . . . . . . 8 ⊢ ((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ ¬ 𝑎 = 𝑏) → 𝑎 ∈ 𝑁)
67		neqne 3024	. . . . . . . . . 10 ⊢ (¬ 𝑎 = 𝑏 → 𝑎 ≠ 𝑏)
68	67	necomd 3071	. . . . . . . . 9 ⊢ (¬ 𝑎 = 𝑏 → 𝑏 ≠ 𝑎)
69	68	adantl 484	. . . . . . . 8 ⊢ ((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ ¬ 𝑎 = 𝑏) → 𝑏 ≠ 𝑎)
70	25, 2, 54, 55, 57, 61, 64, 65, 66, 69	mdetralt2 21212	. . . . . . 7 ⊢ ((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ ¬ 𝑎 = 𝑏) → (𝐷‘(𝑑 ∈ 𝑁, 𝑐 ∈ 𝑁 ↦ if(𝑑 = 𝑏, (𝑎𝑀𝑐), if(𝑑 = 𝑎, (𝑎𝑀𝑐), (𝑑𝑀𝑐))))) = (0g‘𝑅))
71		ifid 4506	. . . . . . . . . . 11 ⊢ if(𝑑 = 𝑎, (𝑑𝑀𝑐), (𝑑𝑀𝑐)) = (𝑑𝑀𝑐)
72		oveq1 7157	. . . . . . . . . . . . 13 ⊢ (𝑑 = 𝑎 → (𝑑𝑀𝑐) = (𝑎𝑀𝑐))
73	72	adantl 484	. . . . . . . . . . . 12 ⊢ (((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ ¬ 𝑎 = 𝑏) ∧ 𝑑 = 𝑎) → (𝑑𝑀𝑐) = (𝑎𝑀𝑐))
74	73	ifeq1da 4497	. . . . . . . . . . 11 ⊢ ((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ ¬ 𝑎 = 𝑏) → if(𝑑 = 𝑎, (𝑑𝑀𝑐), (𝑑𝑀𝑐)) = if(𝑑 = 𝑎, (𝑎𝑀𝑐), (𝑑𝑀𝑐)))
75	71, 74	syl5eqr 2870	. . . . . . . . . 10 ⊢ ((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ ¬ 𝑎 = 𝑏) → (𝑑𝑀𝑐) = if(𝑑 = 𝑎, (𝑎𝑀𝑐), (𝑑𝑀𝑐)))
76	75	ifeq2d 4486	. . . . . . . . 9 ⊢ ((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ ¬ 𝑎 = 𝑏) → if(𝑑 = 𝑏, (𝑎𝑀𝑐), (𝑑𝑀𝑐)) = if(𝑑 = 𝑏, (𝑎𝑀𝑐), if(𝑑 = 𝑎, (𝑎𝑀𝑐), (𝑑𝑀𝑐))))
77	76	mpoeq3dv 7227	. . . . . . . 8 ⊢ ((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ ¬ 𝑎 = 𝑏) → (𝑑 ∈ 𝑁, 𝑐 ∈ 𝑁 ↦ if(𝑑 = 𝑏, (𝑎𝑀𝑐), (𝑑𝑀𝑐))) = (𝑑 ∈ 𝑁, 𝑐 ∈ 𝑁 ↦ if(𝑑 = 𝑏, (𝑎𝑀𝑐), if(𝑑 = 𝑎, (𝑎𝑀𝑐), (𝑑𝑀𝑐)))))
78	77	fveq2d 6669	. . . . . . 7 ⊢ ((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ ¬ 𝑎 = 𝑏) → (𝐷‘(𝑑 ∈ 𝑁, 𝑐 ∈ 𝑁 ↦ if(𝑑 = 𝑏, (𝑎𝑀𝑐), (𝑑𝑀𝑐)))) = (𝐷‘(𝑑 ∈ 𝑁, 𝑐 ∈ 𝑁 ↦ if(𝑑 = 𝑏, (𝑎𝑀𝑐), if(𝑑 = 𝑎, (𝑎𝑀𝑐), (𝑑𝑀𝑐))))))
79		iffalse 4476	. . . . . . . 8 ⊢ (¬ 𝑎 = 𝑏 → if(𝑎 = 𝑏, (𝐷‘𝑀), (0g‘𝑅)) = (0g‘𝑅))
80	79	adantl 484	. . . . . . 7 ⊢ ((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ ¬ 𝑎 = 𝑏) → if(𝑎 = 𝑏, (𝐷‘𝑀), (0g‘𝑅)) = (0g‘𝑅))
81	70, 78, 80	3eqtr4d 2866	. . . . . 6 ⊢ ((((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) ∧ ¬ 𝑎 = 𝑏) → (𝐷‘(𝑑 ∈ 𝑁, 𝑐 ∈ 𝑁 ↦ if(𝑑 = 𝑏, (𝑎𝑀𝑐), (𝑑𝑀𝑐)))) = if(𝑎 = 𝑏, (𝐷‘𝑀), (0g‘𝑅)))
82	53, 81	pm2.61dan 811	. . . . 5 ⊢ (((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) → (𝐷‘(𝑑 ∈ 𝑁, 𝑐 ∈ 𝑁 ↦ if(𝑑 = 𝑏, (𝑎𝑀𝑐), (𝑑𝑀𝑐)))) = if(𝑎 = 𝑏, (𝐷‘𝑀), (0g‘𝑅)))
83	36, 82	eqtrd 2856	. . . 4 ⊢ (((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) → (𝑅 Σg (𝑐 ∈ 𝑁 ↦ ((𝑎𝑀𝑐)(.r‘𝑅)(𝑐(𝐽‘𝑀)𝑏)))) = if(𝑎 = 𝑏, (𝐷‘𝑀), (0g‘𝑅)))
84	83	mpoeq3dva 7225	. . 3 ⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → (𝑎 ∈ 𝑁, 𝑏 ∈ 𝑁 ↦ (𝑅 Σg (𝑐 ∈ 𝑁 ↦ ((𝑎𝑀𝑐)(.r‘𝑅)(𝑐(𝐽‘𝑀)𝑏))))) = (𝑎 ∈ 𝑁, 𝑏 ∈ 𝑁 ↦ if(𝑎 = 𝑏, (𝐷‘𝑀), (0g‘𝑅))))
85		madurid.i	. . . . 5 ⊢ 1 = (1r‘𝐴)
86	85	oveq2i 7161	. . . 4 ⊢ ((𝐷‘𝑀) ∙ 1 ) = ((𝐷‘𝑀) ∙ (1r‘𝐴))
87		crngring 19302	. . . . . 6 ⊢ (𝑅 ∈ CRing → 𝑅 ∈ Ring)
88	87	adantl 484	. . . . 5 ⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → 𝑅 ∈ Ring)
89	25, 5, 6, 2	mdetf 21198	. . . . . . 7 ⊢ (𝑅 ∈ CRing → 𝐷:𝐵⟶(Base‘𝑅))
90	89	adantl 484	. . . . . 6 ⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → 𝐷:𝐵⟶(Base‘𝑅))
91	90, 15	ffvelrnd 6847	. . . . 5 ⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → (𝐷‘𝑀) ∈ (Base‘𝑅))
92		madurid.s	. . . . . 6 ⊢ ∙ = ( ·𝑠 ‘𝐴)
93	5, 2, 92, 54	matsc 21053	. . . . 5 ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ (𝐷‘𝑀) ∈ (Base‘𝑅)) → ((𝐷‘𝑀) ∙ (1r‘𝐴)) = (𝑎 ∈ 𝑁, 𝑏 ∈ 𝑁 ↦ if(𝑎 = 𝑏, (𝐷‘𝑀), (0g‘𝑅))))
94	9, 88, 91, 93	syl3anc 1367	. . . 4 ⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → ((𝐷‘𝑀) ∙ (1r‘𝐴)) = (𝑎 ∈ 𝑁, 𝑏 ∈ 𝑁 ↦ if(𝑎 = 𝑏, (𝐷‘𝑀), (0g‘𝑅))))
95	86, 94	syl5eq 2868	. . 3 ⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → ((𝐷‘𝑀) ∙ 1 ) = (𝑎 ∈ 𝑁, 𝑏 ∈ 𝑁 ↦ if(𝑎 = 𝑏, (𝐷‘𝑀), (0g‘𝑅))))
96	84, 95	eqtr4d 2859	. 2 ⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → (𝑎 ∈ 𝑁, 𝑏 ∈ 𝑁 ↦ (𝑅 Σg (𝑐 ∈ 𝑁 ↦ ((𝑎𝑀𝑐)(.r‘𝑅)(𝑐(𝐽‘𝑀)𝑏))))) = ((𝐷‘𝑀) ∙ 1 ))
97	19, 24, 96	3eqtr3d 2864	1 ⊢ ((𝑀 ∈ 𝐵 ∧ 𝑅 ∈ CRing) → (𝑀 · (𝐽‘𝑀)) = ((𝐷‘𝑀) ∙ 1 ))

Syntax hints:  ¬ wn 3   → wi 4   ∧ wa 398   ∧ w3a 1083   = wceq 1533   ∈ wcel 2110   ≠ wne 3016  Vcvv 3495  ifcif 4467  ⟨cotp 4569   ↦ cmpt 5139   × cxp 5548   Fn wfn 6345  ⟶wf 6346  ‘cfv 6350  (class class class)co 7150   ∈ cmpo 7152   ↑_m cmap 8400  Fincfn 8503  Basecbs 16477  ._rcmulr 16560   ·_𝑠 cvsca 16563  0_gc0g 16707   Σ_g cgsu 16708  1_rcur 19245  Ringcrg 19291  CRingccrg 19292   maMul cmmul 20988   Mat cmat 21010   maDet cmdat 21187   maAdju cmadu 21235

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1792  ax-4 1806  ax-5 1907  ax-6 1966  ax-7 2011  ax-8 2112  ax-9 2120  ax-10 2141  ax-11 2156  ax-12 2172  ax-ext 2793  ax-rep 5183  ax-sep 5196  ax-nul 5203  ax-pow 5259  ax-pr 5322  ax-un 7455  ax-cnex 10587  ax-resscn 10588  ax-1cn 10589  ax-icn 10590  ax-addcl 10591  ax-addrcl 10592  ax-mulcl 10593  ax-mulrcl 10594  ax-mulcom 10595  ax-addass 10596  ax-mulass 10597  ax-distr 10598  ax-i2m1 10599  ax-1ne0 10600  ax-1rid 10601  ax-rnegex 10602  ax-rrecex 10603  ax-cnre 10604  ax-pre-lttri 10605  ax-pre-lttrn 10606  ax-pre-ltadd 10607  ax-pre-mulgt0 10608  ax-addf 10610  ax-mulf 10611

This theorem depends on definitions:  df-bi 209  df-an 399  df-or 844  df-3or 1084  df-3an 1085  df-xor 1501  df-tru 1536  df-fal 1546  df-ex 1777  df-nf 1781  df-sb 2066  df-mo 2618  df-eu 2650  df-clab 2800  df-cleq 2814  df-clel 2893  df-nfc 2963  df-ne 3017  df-nel 3124  df-ral 3143  df-rex 3144  df-reu 3145  df-rmo 3146  df-rab 3147  df-v 3497  df-sbc 3773  df-csb 3884  df-dif 3939  df-un 3941  df-in 3943  df-ss 3952  df-pss 3954  df-nul 4292  df-if 4468  df-pw 4541  df-sn 4562  df-pr 4564  df-tp 4566  df-op 4568  df-ot 4570  df-uni 4833  df-int 4870  df-iun 4914  df-iin 4915  df-br 5060  df-opab 5122  df-mpt 5140  df-tr 5166  df-id 5455  df-eprel 5460  df-po 5469  df-so 5470  df-fr 5509  df-se 5510  df-we 5511  df-xp 5556  df-rel 5557  df-cnv 5558  df-co 5559  df-dm 5560  df-rn 5561  df-res 5562  df-ima 5563  df-pred 6143  df-ord 6189  df-on 6190  df-lim 6191  df-suc 6192  df-iota 6309  df-fun 6352  df-fn 6353  df-f 6354  df-f1 6355  df-fo 6356  df-f1o 6357  df-fv 6358  df-isom 6359  df-riota 7108  df-ov 7153  df-oprab 7154  df-mpo 7155  df-of 7403  df-om 7575  df-1st 7683  df-2nd 7684  df-supp 7825  df-tpos 7886  df-wrecs 7941  df-recs 8002  df-rdg 8040  df-1o 8096  df-2o 8097  df-oadd 8100  df-er 8283  df-map 8402  df-pm 8403  df-ixp 8456  df-en 8504  df-dom 8505  df-sdom 8506  df-fin 8507  df-fsupp 8828  df-sup 8900  df-oi 8968  df-card 9362  df-pnf 10671  df-mnf 10672  df-xr 10673  df-ltxr 10674  df-le 10675  df-sub 10866  df-neg 10867  df-div 11292  df-nn 11633  df-2 11694  df-3 11695  df-4 11696  df-5 11697  df-6 11698  df-7 11699  df-8 11700  df-9 11701  df-n0 11892  df-xnn0 11962  df-z 11976  df-dec 12093  df-uz 12238  df-rp 12384  df-fz 12887  df-fzo 13028  df-seq 13364  df-exp 13424  df-hash 13685  df-word 13856  df-lsw 13909  df-concat 13917  df-s1 13944  df-substr 13997  df-pfx 14027  df-splice 14106  df-reverse 14115  df-s2 14204  df-struct 16479  df-ndx 16480  df-slot 16481  df-base 16483  df-sets 16484  df-ress 16485  df-plusg 16572  df-mulr 16573  df-starv 16574  df-sca 16575  df-vsca 16576  df-ip 16577  df-tset 16578  df-ple 16579  df-ds 16581  df-unif 16582  df-hom 16583  df-cco 16584  df-0g 16709  df-gsum 16710  df-prds 16715  df-pws 16717  df-mre 16851  df-mrc 16852  df-acs 16854  df-mgm 17846  df-sgrp 17895  df-mnd 17906  df-mhm 17950  df-submnd 17951  df-efmnd 18028  df-grp 18100  df-minusg 18101  df-sbg 18102  df-mulg 18219  df-subg 18270  df-ghm 18350  df-gim 18393  df-cntz 18441  df-oppg 18468  df-symg 18490  df-pmtr 18564  df-psgn 18613  df-evpm 18614  df-cmn 18902  df-abl 18903  df-mgp 19234  df-ur 19246  df-ring 19293  df-cring 19294  df-oppr 19367  df-dvdsr 19385  df-unit 19386  df-invr 19416  df-dvr 19427  df-rnghom 19461  df-drng 19498  df-subrg 19527  df-lmod 19630  df-lss 19698  df-sra 19938  df-rgmod 19939  df-cnfld 20540  df-zring 20612  df-zrh 20645  df-dsmm 20870  df-frlm 20885  df-mamu 20989  df-mat 21011  df-mdet 21188  df-madu 21237

This theorem is referenced by:  madulid  21248  matinv  21280  cpmadurid  21469  cpmidgsum2  21481