| Step | Hyp | Ref
 | Expression | 
| 1 |   | unitpropdg.1 | 
. . . . . . 7
                  | 
| 2 |   | unitpropdg.2 | 
. . . . . . 7
                  | 
| 3 |   | unitpropdg.3 | 
. . . . . . 7
       
      
                                   | 
| 4 |   | unitpropdg.k | 
. . . . . . 7
              | 
| 5 |   | unitpropdg.l | 
. . . . . . 7
              | 
| 6 | 1, 2, 3, 4, 5 | rngidpropdg 13702 | 
. . . . . 6
                      | 
| 7 | 6 | breq2d 4045 | 
. . . . 5
           r          
   r           | 
| 8 | 6 | breq2d 4045 | 
. . . . 5
           r  oppr           
   r  oppr            | 
| 9 | 7, 8 | anbi12d 473 | 
. . . 4
            r              r  oppr            
    r              r  oppr             | 
| 10 |   | ringsrg 13603 | 
. . . . . . . 8
        
      SRing  | 
| 11 | 4, 10 | syl 14 | 
. . . . . . 7
           SRing  | 
| 12 |   | ringsrg 13603 | 
. . . . . . . 8
        
      SRing  | 
| 13 | 5, 12 | syl 14 | 
. . . . . . 7
           SRing  | 
| 14 | 1, 2, 3, 11, 13 | dvdsrpropdg 13703 | 
. . . . . 6
         r        r     | 
| 15 | 14 | breqd 4044 | 
. . . . 5
           r          
   r           | 
| 16 |   | eqid 2196 | 
. . . . . . . . . 10
   oppr       oppr    | 
| 17 |   | eqid 2196 | 
. . . . . . . . . 10
                | 
| 18 | 16, 17 | opprbasg 13631 | 
. . . . . . . . 9
        
              oppr      | 
| 19 | 4, 18 | syl 14 | 
. . . . . . . 8
                   oppr      | 
| 20 | 1, 19 | eqtrd 2229 | 
. . . . . . 7
               oppr      | 
| 21 |   | eqid 2196 | 
. . . . . . . . . 10
   oppr       oppr    | 
| 22 |   | eqid 2196 | 
. . . . . . . . . 10
                | 
| 23 | 21, 22 | opprbasg 13631 | 
. . . . . . . . 9
        
              oppr      | 
| 24 | 5, 23 | syl 14 | 
. . . . . . . 8
                   oppr      | 
| 25 | 2, 24 | eqtrd 2229 | 
. . . . . . 7
               oppr      | 
| 26 | 3 | ancom2s 566 | 
. . . . . . . 8
       
      
                                   | 
| 27 | 4 | adantr 276 | 
. . . . . . . . 9
       
      
               
   | 
| 28 |   | simprl 529 | 
. . . . . . . . 9
       
      
                   | 
| 29 |   | simprr 531 | 
. . . . . . . . 9
       
      
               
   | 
| 30 |   | eqid 2196 | 
. . . . . . . . . 10
                | 
| 31 |   | eqid 2196 | 
. . . . . . . . . 10
      oppr           oppr     | 
| 32 | 17, 30, 16, 31 | opprmulg 13627 | 
. . . . . . . . 9
                 
                 oppr                    | 
| 33 | 27, 28, 29, 32 | syl3anc 1249 | 
. . . . . . . 8
       
      
                  oppr                    | 
| 34 | 5 | adantr 276 | 
. . . . . . . . 9
       
      
               
   | 
| 35 |   | eqid 2196 | 
. . . . . . . . . 10
                | 
| 36 |   | eqid 2196 | 
. . . . . . . . . 10
      oppr           oppr     | 
| 37 | 22, 35, 21, 36 | opprmulg 13627 | 
. . . . . . . . 9
                 
                 oppr                    | 
| 38 | 34, 28, 29, 37 | syl3anc 1249 | 
. . . . . . . 8
       
      
                  oppr                    | 
| 39 | 26, 33, 38 | 3eqtr4d 2239 | 
. . . . . . 7
       
      
                  oppr               oppr        | 
| 40 | 16 | opprring 13635 | 
. . . . . . . 8
        
   oppr         | 
| 41 |   | ringsrg 13603 | 
. . . . . . . 8
    oppr           oppr      SRing  | 
| 42 | 4, 40, 41 | 3syl 17 | 
. . . . . . 7
        oppr      SRing  | 
| 43 | 21 | opprring 13635 | 
. . . . . . . 8
        
   oppr         | 
| 44 |   | ringsrg 13603 | 
. . . . . . . 8
    oppr           oppr      SRing  | 
| 45 | 5, 43, 44 | 3syl 17 | 
. . . . . . 7
        oppr      SRing  | 
| 46 | 20, 25, 39, 42, 45 | dvdsrpropdg 13703 | 
. . . . . 6
         r  oppr         r  oppr      | 
| 47 | 46 | breqd 4044 | 
. . . . 5
           r  oppr           
   r  oppr            | 
| 48 | 15, 47 | anbi12d 473 | 
. . . 4
            r              r  oppr            
    r              r  oppr             | 
| 49 | 9, 48 | bitrd 188 | 
. . 3
            r              r  oppr            
    r              r  oppr             | 
| 50 |   | eqidd 2197 | 
. . . 4
        Unit       Unit     | 
| 51 |   | eqidd 2197 | 
. . . 4
                      | 
| 52 |   | eqidd 2197 | 
. . . 4
         r        r     | 
| 53 |   | eqidd 2197 | 
. . . 4
        oppr       oppr     | 
| 54 |   | eqidd 2197 | 
. . . 4
         r  oppr         r  oppr      | 
| 55 | 50, 51, 52, 53, 54, 11 | isunitd 13662 | 
. . 3
             Unit     
    r              r  oppr             | 
| 56 |   | eqidd 2197 | 
. . . 4
        Unit       Unit     | 
| 57 |   | eqidd 2197 | 
. . . 4
                      | 
| 58 |   | eqidd 2197 | 
. . . 4
         r        r     | 
| 59 |   | eqidd 2197 | 
. . . 4
        oppr       oppr     | 
| 60 |   | eqidd 2197 | 
. . . 4
         r  oppr         r  oppr      | 
| 61 | 56, 57, 58, 59, 60, 13 | isunitd 13662 | 
. . 3
             Unit     
    r              r  oppr             | 
| 62 | 49, 55, 61 | 3bitr4d 220 | 
. 2
             Unit     
     Unit      | 
| 63 | 62 | eqrdv 2194 | 
1
        Unit       Unit     |