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Theorem mulcan 5610
Description: Cancellation law for multiplication. Theorem I.7 of [Apostol] p. 18.
Hypotheses
Ref Expression
mulcan.1 |- A e. CC
mulcan.2 |- B e. CC
mulcan.3 |- C e. CC
mulcan.4 |- A =/= 0
Assertion
Ref Expression
mulcan |- ((A x. B) = (A x. C) <-> B = C)

Proof of Theorem mulcan
StepHypRef Expression
1 mulcan.1 . . . 4 |- A e. CC
2 mulcan.4 . . . 4 |- A =/= 0
31, 2recex 5609 . . 3 |- E.x e. CC (A x. x) = 1
4 mulcan.2 . . . . . . . . . 10 |- B e. CC
5 axmulass 5201 . . . . . . . . . 10 |- ((x e. CC /\ A e. CC /\ B e. CC) -> ((x x. A) x. B) = (x x. (A x. B)))
64, 5mp3an3 901 . . . . . . . . 9 |- ((x e. CC /\ A e. CC) -> ((x x. A) x. B) = (x x. (A x. B)))
7 mulcan.3 . . . . . . . . . 10 |- C e. CC
8 axmulass 5201 . . . . . . . . . 10 |- ((x e. CC /\ A e. CC /\ C e. CC) -> ((x x. A) x. C) = (x x. (A x. C)))
97, 8mp3an3 901 . . . . . . . . 9 |- ((x e. CC /\ A e. CC) -> ((x x. A) x. C) = (x x. (A x. C)))
106, 9eqeq12d 1465 . . . . . . . 8 |- ((x e. CC /\ A e. CC) -> (((x x. A) x. B) = ((x x. A) x. C) <-> (x x. (A x. B)) = (x x. (A x. C))))
111, 10mpan2 693 . . . . . . 7 |- (x e. CC -> (((x x. A) x. B) = ((x x. A) x. C) <-> (x x. (A x. B)) = (x x. (A x. C))))
12 opreq2 3908 . . . . . . 7 |- ((A x. B) = (A x. C) -> (x x. (A x. B)) = (x x. (A x. C)))
1311, 12syl5bir 210 . . . . . 6 |- (x e. CC -> ((A x. B) = (A x. C) -> ((x x. A) x. B) = ((x x. A) x. C)))
1413adantr 389 . . . . 5 |- ((x e. CC /\ (A x. x) = 1) -> ((A x. B) = (A x. C) -> ((x x. A) x. B) = ((x x. A) x. C)))
15 axmulcom 5199 . . . . . . . . 9 |- ((A e. CC /\ x e. CC) -> (A x. x) = (x x. A))
161, 15mpan 692 . . . . . . . 8 |- (x e. CC -> (A x. x) = (x x. A))
1716eqeq1d 1459 . . . . . . 7 |- (x e. CC -> ((A x. x) = 1 <-> (x x. A) = 1))
18 opreq1 3907 . . . . . . . . 9 |- ((x x. A) = 1 -> ((x x. A) x. B) = (1 x. B))
194mulid2 5256 . . . . . . . . 9 |- (1 x. B) = B
2018, 19syl6eq 1499 . . . . . . . 8 |- ((x x. A) = 1 -> ((x x. A) x. B) = B)
21 opreq1 3907 . . . . . . . . 9 |- ((x x. A) = 1 -> ((x x. A) x. C) = (1 x. C))
227mulid2 5256 . . . . . . . . 9 |- (1 x. C) = C
2321, 22syl6eq 1499 . . . . . . . 8 |- ((x x. A) = 1 -> ((x x. A) x. C) = C)
2420, 23eqeq12d 1465 . . . . . . 7 |- ((x x. A) = 1 -> (((x x. A) x. B) = ((x x. A) x. C) <-> B = C))
2517, 24syl6bi 214 . . . . . 6 |- (x e. CC -> ((A x. x) = 1 -> (((x x. A) x. B) = ((x x. A) x. C) <-> B = C)))
2625imp 350 . . . . 5 |- ((x e. CC /\ (A x. x) = 1) -> (((x x. A) x. B) = ((x x. A) x. C) <-> B = C))
2714, 26sylibd 202 . . . 4 |- ((x e. CC /\ (A x. x) = 1) -> ((A x. B) = (A x. C) -> B = C))
2827r19.23aiva 1720 . . 3 |- (E.x e. CC (A x. x) = 1 -> ((A x. B) = (A x. C) -> B = C))
293, 28ax-mp 7 . 2 |- ((A x. B) = (A x. C) -> B = C)
30 opreq2 3908 . 2 |- (B = C -> (A x. B) = (A x. C))
3129, 30impbi 157 1 |- ((A x. B) = (A x. C) <-> B = C)
Colors of variables: wff set class
Syntax hints:   -> wi 3   <-> wb 146   /\ wa 223   = wceq 1099   e. wcel 1105   =/= wne 1561  E.wrex 1622  (class class class)co 3902  CCcc 5155  0cc0 5157  1c1 5158   x. cmul 5162
This theorem is referenced by:  mulcant2 5611  div11 5671  sqr2irrlem1 6605  cjreb 6667  0.999... 7132  ipasslem10 8365
This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-3 6  ax-mp 7  ax-4 951  ax-5 952  ax-6 953  ax-7 954  ax-gen 955  ax-8 1101  ax-9 1102  ax-10 1103  ax-12 1104  ax-13 1107  ax-14 1108  ax-11 1180  ax-17 1190  ax-16 1194  ax-11o 1202  ax-ext 1436  ax-rep 2661  ax-sep 2671  ax-nul 2678  ax-pow 2710  ax-pr 2747  ax-un 2830  ax-inf2 4549
This theorem depends on definitions:  df-bi 147  df-or 224  df-an 225  df-3or 773  df-3an 774  df-ex 957  df-sb 1155  df-eu 1359  df-mo 1360  df-clab 1441  df-cleq 1446  df-clel 1449  df-ne 1563  df-nel 1564  df-ral 1625  df-rex 1626  df-reu 1627  df-rab 1628  df-v 1787  df-sbc 1913  df-csb 1973  df-dif 2020  df-un 2021  df-in 2022  df-ss 2024  df-pss 2026  df-nul 2252  df-if 2333  df-pw 2373  df-sn 2383  df-pr 2384  df-tp 2386  df-op 2387  df-uni 2472  df-int 2502  df-iun 2536  df-br 2588  df-opab 2635  df-tr 2649  df-eprel 2794  df-id 2797  df-po 2804  df-so 2814  df-fr 2880  df-we 2897  df-ord 2914  df-on 2915  df-lim 2916  df-suc 2917  df-om 3095  df-xp 3147  df-rel 3148  df-cnv 3149  df-co 3150  df-dm 3151  df-rn 3152  df-res 3153  df-ima 3154  df-fun 3155  df-fn 3156  df-f 3157  df-f1 3158  df-fo 3159  df-f1o 3160  df-fv 3161  df-rdg 3871  df-opr 3904  df-oprab 3905  df-1st 4017  df-2nd 4018  df-1o 4071  df-oadd 4073  df-omul 4074  df-er 4199  df-ec 4201  df-qs 4204  df-en 4305  df-dom 4306  df-sdom 4307  df-ni 4923  df-pli 4924  df-mi 4925  df-lti 4926  df-plpq 4958  df-mpq 4959  df-enq 4960  df-nq 4961  df-plq 4962  df-mq 4963  df-rq 4964  df-ltq 4965  df-1q 4966  df-np 5009  df-1p 5010  df-plp 5011  df-mp 5012  df-ltp 5013  df-plpr 5087  df-mpr 5088  df-enr 5089  df-nr 5090  df-plr 5091  df-mr 5092  df-ltr 5093  df-0r 5094  df-1r 5095  df-m1r 5096  df-c 5163  df-0 5164  df-1 5165  df-i 5166  df-r 5167  df-plus 5168  df-mul 5169  df-lt 5170  df-sub 5279  df-neg 5281  df-pnf 5410  df-mnf 5411  df-xr 5412  df-ltxr 5413  df-le 5414
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