| Step | Hyp | Ref | Expression | 
						
							| 1 |  | pmtrdifel.t |  | 
						
							| 2 |  | pmtrdifel.r |  | 
						
							| 3 |  | pmtrdifwrdel.0 |  | 
						
							| 4 |  | wrdsymbcl |  | 
						
							| 5 |  | eqid |  | 
						
							| 6 | 1 2 5 | pmtrdifellem3 |  | 
						
							| 7 | 4 6 | syl |  | 
						
							| 8 |  | fveq2 |  | 
						
							| 9 | 8 | difeq1d |  | 
						
							| 10 | 9 | dmeqd |  | 
						
							| 11 | 10 | fveq2d |  | 
						
							| 12 |  | simpr |  | 
						
							| 13 |  | fvexd |  | 
						
							| 14 | 3 11 12 13 | fvmptd3 |  | 
						
							| 15 | 14 | fveq1d |  | 
						
							| 16 | 15 | eqeq2d |  | 
						
							| 17 | 16 | ralbidv |  | 
						
							| 18 | 7 17 | mpbird |  | 
						
							| 19 | 18 | ralrimiva |  |