Metamath Proof Explorer


Theorem r1pid2

Description: Identity law for polynomial remainder operation: it leaves a polynomial A unchanged iff the degree of A is less than the degree of the divisor B . (Contributed by Thierry Arnoux, 2-Apr-2025)

Ref Expression
Hypotheses r1padd1.p P = Poly 1 R
r1padd1.u U = Base P
r1padd1.n N = Unic 1p R
r1padd1.e E = rem 1p R
r1pid2.r φ R IDomn
r1pid2.d D = deg 1 R
r1pid2.p φ A U
r1pid2.q φ B N
Assertion r1pid2 φ A E B = A D A < D B

Proof

Step Hyp Ref Expression
1 r1padd1.p P = Poly 1 R
2 r1padd1.u U = Base P
3 r1padd1.n N = Unic 1p R
4 r1padd1.e E = rem 1p R
5 r1pid2.r φ R IDomn
6 r1pid2.d D = deg 1 R
7 r1pid2.p φ A U
8 r1pid2.q φ B N
9 5 idomringd φ R Ring
10 eqid quot 1p R = quot 1p R
11 eqid P = P
12 eqid + P = + P
13 1 2 3 10 4 11 12 r1pid R Ring A U B N A = A quot 1p R B P B + P A E B
14 9 7 8 13 syl3anc φ A = A quot 1p R B P B + P A E B
15 14 eqeq2d φ A E B = A A E B = A quot 1p R B P B + P A E B
16 eqcom A quot 1p R B P B + P A E B = A E B A E B = A quot 1p R B P B + P A E B
17 15 16 bitr4di φ A E B = A A quot 1p R B P B + P A E B = A E B
18 eqid 0 P = 0 P
19 1 ply1ring R Ring P Ring
20 9 19 syl φ P Ring
21 20 ringgrpd φ P Grp
22 4 1 2 3 r1pcl R Ring A U B N A E B U
23 9 7 8 22 syl3anc φ A E B U
24 2 12 18 21 23 grplidd φ 0 P + P A E B = A E B
25 24 eqeq2d φ A quot 1p R B P B + P A E B = 0 P + P A E B A quot 1p R B P B + P A E B = A E B
26 10 1 2 3 q1pcl R Ring A U B N A quot 1p R B U
27 9 7 8 26 syl3anc φ A quot 1p R B U
28 1 2 3 uc1pcl B N B U
29 8 28 syl φ B U
30 2 11 20 27 29 ringcld φ A quot 1p R B P B U
31 2 18 ring0cl P Ring 0 P U
32 9 19 31 3syl φ 0 P U
33 2 12 grprcan P Grp A quot 1p R B P B U 0 P U A E B U A quot 1p R B P B + P A E B = 0 P + P A E B A quot 1p R B P B = 0 P
34 21 30 32 23 33 syl13anc φ A quot 1p R B P B + P A E B = 0 P + P A E B A quot 1p R B P B = 0 P
35 17 25 34 3bitr2d φ A E B = A A quot 1p R B P B = 0 P
36 isidom R IDomn R CRing R Domn
37 5 36 sylib φ R CRing R Domn
38 37 simpld φ R CRing
39 1 ply1crng R CRing P CRing
40 38 39 syl φ P CRing
41 2 11 crngcom P CRing B U A quot 1p R B U B P A quot 1p R B = A quot 1p R B P B
42 40 29 27 41 syl3anc φ B P A quot 1p R B = A quot 1p R B P B
43 42 eqeq1d φ B P A quot 1p R B = 0 P A quot 1p R B P B = 0 P
44 5 idomdomd φ R Domn
45 1 ply1domn R Domn P Domn
46 44 45 syl φ P Domn
47 1 18 3 uc1pn0 B N B 0 P
48 8 47 syl φ B 0 P
49 eqid RLReg P = RLReg P
50 2 49 18 domnrrg P Domn B U B 0 P B RLReg P
51 46 29 48 50 syl3anc φ B RLReg P
52 49 2 11 18 rrgeq0 P Ring B RLReg P A quot 1p R B U B P A quot 1p R B = 0 P A quot 1p R B = 0 P
53 20 51 27 52 syl3anc φ B P A quot 1p R B = 0 P A quot 1p R B = 0 P
54 35 43 53 3bitr2d φ A E B = A A quot 1p R B = 0 P
55 2 11 18 20 29 ringlzd φ 0 P P B = 0 P
56 55 oveq2d φ A - P 0 P P B = A - P 0 P
57 eqid - P = - P
58 2 18 57 grpsubid1 P Grp A U A - P 0 P = A
59 21 7 58 syl2anc φ A - P 0 P = A
60 56 59 eqtr2d φ A = A - P 0 P P B
61 60 fveq2d φ D A = D A - P 0 P P B
62 61 breq1d φ D A < D B D A - P 0 P P B < D B
63 32 biantrurd φ D A - P 0 P P B < D B 0 P U D A - P 0 P P B < D B
64 10 1 2 6 57 11 3 q1peqb R Ring A U B N 0 P U D A - P 0 P P B < D B A quot 1p R B = 0 P
65 9 7 8 64 syl3anc φ 0 P U D A - P 0 P P B < D B A quot 1p R B = 0 P
66 62 63 65 3bitrd φ D A < D B A quot 1p R B = 0 P
67 54 66 bitr4d φ A E B = A D A < D B