Theorem readdcan 8254

Description: Cancellation law for addition over the reals. (Contributed by Scott Fenton, 3-Jan-2013.)

Assertion

Ref	Expression
readdcan	⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → ((𝐶 + 𝐴) = (𝐶 + 𝐵) ↔ 𝐴 = 𝐵))

Proof of Theorem readdcan

Dummy variable 𝑥 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		ax-rnegex 8076	. . . 4 ⊢ (𝐶 ∈ ℝ → ∃𝑥 ∈ ℝ (𝐶 + 𝑥) = 0)
2	1	3ad2ant3 1025	. . 3 ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → ∃𝑥 ∈ ℝ (𝐶 + 𝑥) = 0)
3		oveq2 5982	. . . . . . 7 ⊢ ((𝐶 + 𝐴) = (𝐶 + 𝐵) → (𝑥 + (𝐶 + 𝐴)) = (𝑥 + (𝐶 + 𝐵)))
4	3	adantl 277	. . . . . 6 ⊢ ((((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) ∧ (𝐶 + 𝐴) = (𝐶 + 𝐵)) → (𝑥 + (𝐶 + 𝐴)) = (𝑥 + (𝐶 + 𝐵)))
5		simprl 529	. . . . . . . . . 10 ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) → 𝑥 ∈ ℝ)
6	5	recnd 8143	. . . . . . . . 9 ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) → 𝑥 ∈ ℂ)
7		simpl3 1007	. . . . . . . . . 10 ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) → 𝐶 ∈ ℝ)
8	7	recnd 8143	. . . . . . . . 9 ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) → 𝐶 ∈ ℂ)
9		simpl1 1005	. . . . . . . . . 10 ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) → 𝐴 ∈ ℝ)
10	9	recnd 8143	. . . . . . . . 9 ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) → 𝐴 ∈ ℂ)
11	6, 8, 10	addassd 8137	. . . . . . . 8 ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) → ((𝑥 + 𝐶) + 𝐴) = (𝑥 + (𝐶 + 𝐴)))
12		simpl2 1006	. . . . . . . . . 10 ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) → 𝐵 ∈ ℝ)
13	12	recnd 8143	. . . . . . . . 9 ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) → 𝐵 ∈ ℂ)
14	6, 8, 13	addassd 8137	. . . . . . . 8 ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) → ((𝑥 + 𝐶) + 𝐵) = (𝑥 + (𝐶 + 𝐵)))
15	11, 14	eqeq12d 2224	. . . . . . 7 ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) → (((𝑥 + 𝐶) + 𝐴) = ((𝑥 + 𝐶) + 𝐵) ↔ (𝑥 + (𝐶 + 𝐴)) = (𝑥 + (𝐶 + 𝐵))))
16	15	adantr 276	. . . . . 6 ⊢ ((((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) ∧ (𝐶 + 𝐴) = (𝐶 + 𝐵)) → (((𝑥 + 𝐶) + 𝐴) = ((𝑥 + 𝐶) + 𝐵) ↔ (𝑥 + (𝐶 + 𝐴)) = (𝑥 + (𝐶 + 𝐵))))
17	4, 16	mpbird 167	. . . . 5 ⊢ ((((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) ∧ (𝐶 + 𝐴) = (𝐶 + 𝐵)) → ((𝑥 + 𝐶) + 𝐴) = ((𝑥 + 𝐶) + 𝐵))
18	8	adantr 276	. . . . . . . . 9 ⊢ ((((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) ∧ (𝐶 + 𝐴) = (𝐶 + 𝐵)) → 𝐶 ∈ ℂ)
19	6	adantr 276	. . . . . . . . 9 ⊢ ((((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) ∧ (𝐶 + 𝐴) = (𝐶 + 𝐵)) → 𝑥 ∈ ℂ)
20		addcom 8251	. . . . . . . . 9 ⊢ ((𝐶 ∈ ℂ ∧ 𝑥 ∈ ℂ) → (𝐶 + 𝑥) = (𝑥 + 𝐶))
21	18, 19, 20	syl2anc 411	. . . . . . . 8 ⊢ ((((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) ∧ (𝐶 + 𝐴) = (𝐶 + 𝐵)) → (𝐶 + 𝑥) = (𝑥 + 𝐶))
22		simplrr 536	. . . . . . . 8 ⊢ ((((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) ∧ (𝐶 + 𝐴) = (𝐶 + 𝐵)) → (𝐶 + 𝑥) = 0)
23	21, 22	eqtr3d 2244	. . . . . . 7 ⊢ ((((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) ∧ (𝐶 + 𝐴) = (𝐶 + 𝐵)) → (𝑥 + 𝐶) = 0)
24	23	oveq1d 5989	. . . . . 6 ⊢ ((((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) ∧ (𝐶 + 𝐴) = (𝐶 + 𝐵)) → ((𝑥 + 𝐶) + 𝐴) = (0 + 𝐴))
25	10	adantr 276	. . . . . . 7 ⊢ ((((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) ∧ (𝐶 + 𝐴) = (𝐶 + 𝐵)) → 𝐴 ∈ ℂ)
26		addlid 8253	. . . . . . 7 ⊢ (𝐴 ∈ ℂ → (0 + 𝐴) = 𝐴)
27	25, 26	syl 14	. . . . . 6 ⊢ ((((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) ∧ (𝐶 + 𝐴) = (𝐶 + 𝐵)) → (0 + 𝐴) = 𝐴)
28	24, 27	eqtrd 2242	. . . . 5 ⊢ ((((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) ∧ (𝐶 + 𝐴) = (𝐶 + 𝐵)) → ((𝑥 + 𝐶) + 𝐴) = 𝐴)
29	23	oveq1d 5989	. . . . . 6 ⊢ ((((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) ∧ (𝐶 + 𝐴) = (𝐶 + 𝐵)) → ((𝑥 + 𝐶) + 𝐵) = (0 + 𝐵))
30	13	adantr 276	. . . . . . 7 ⊢ ((((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) ∧ (𝐶 + 𝐴) = (𝐶 + 𝐵)) → 𝐵 ∈ ℂ)
31		addlid 8253	. . . . . . 7 ⊢ (𝐵 ∈ ℂ → (0 + 𝐵) = 𝐵)
32	30, 31	syl 14	. . . . . 6 ⊢ ((((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) ∧ (𝐶 + 𝐴) = (𝐶 + 𝐵)) → (0 + 𝐵) = 𝐵)
33	29, 32	eqtrd 2242	. . . . 5 ⊢ ((((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) ∧ (𝐶 + 𝐴) = (𝐶 + 𝐵)) → ((𝑥 + 𝐶) + 𝐵) = 𝐵)
34	17, 28, 33	3eqtr3d 2250	. . . 4 ⊢ ((((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) ∧ (𝐶 + 𝐴) = (𝐶 + 𝐵)) → 𝐴 = 𝐵)
35	34	ex 115	. . 3 ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) ∧ (𝑥 ∈ ℝ ∧ (𝐶 + 𝑥) = 0)) → ((𝐶 + 𝐴) = (𝐶 + 𝐵) → 𝐴 = 𝐵))
36	2, 35	rexlimddv 2633	. 2 ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → ((𝐶 + 𝐴) = (𝐶 + 𝐵) → 𝐴 = 𝐵))
37		oveq2 5982	. 2 ⊢ (𝐴 = 𝐵 → (𝐶 + 𝐴) = (𝐶 + 𝐵))
38	36, 37	impbid1 142	1 ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → ((𝐶 + 𝐴) = (𝐶 + 𝐵) ↔ 𝐴 = 𝐵))

Syntax hints:   → wi 4   ∧ wa 104   ↔ wb 105   ∧ w3a 983   = wceq 1375   ∈ wcel 2180  ∃wrex 2489  (class class class)co 5974  ℂcc 7965  ℝcr 7966  0cc0 7967   + caddc 7970

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 713  ax-5 1473  ax-7 1474  ax-gen 1475  ax-ie1 1519  ax-ie2 1520  ax-8 1530  ax-10 1531  ax-11 1532  ax-i12 1533  ax-bndl 1535  ax-4 1536  ax-17 1552  ax-i9 1556  ax-ial 1560  ax-i5r 1561  ax-ext 2191  ax-resscn 8059  ax-1cn 8060  ax-icn 8062  ax-addcl 8063  ax-mulcl 8065  ax-addcom 8067  ax-addass 8069  ax-i2m1 8072  ax-0id 8075  ax-rnegex 8076

This theorem depends on definitions:  df-bi 117  df-3an 985  df-tru 1378  df-nf 1487  df-sb 1789  df-clab 2196  df-cleq 2202  df-clel 2205  df-nfc 2341  df-ral 2493  df-rex 2494  df-v 2781  df-un 3181  df-in 3183  df-ss 3190  df-sn 3652  df-pr 3653  df-op 3655  df-uni 3868  df-br 4063  df-iota 5254  df-fv 5302  df-ov 5977

This theorem is referenced by: (None)