This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.
Description: The center of a group is the same as the center of the opposite group. (Contributed by Mario Carneiro, 21-Apr-2016)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | oppggic.o | ⊢ 𝑂 = ( oppg ‘ 𝐺 ) | |
| oppgcntr.z | ⊢ 𝑍 = ( Cntr ‘ 𝐺 ) | ||
| Assertion | oppgcntr | ⊢ 𝑍 = ( Cntr ‘ 𝑂 ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | oppggic.o | ⊢ 𝑂 = ( oppg ‘ 𝐺 ) | |
| 2 | oppgcntr.z | ⊢ 𝑍 = ( Cntr ‘ 𝐺 ) | |
| 3 | eqid | ⊢ ( Cntz ‘ 𝐺 ) = ( Cntz ‘ 𝐺 ) | |
| 4 | 1 3 | oppgcntz | ⊢ ( ( Cntz ‘ 𝐺 ) ‘ ( Base ‘ 𝐺 ) ) = ( ( Cntz ‘ 𝑂 ) ‘ ( Base ‘ 𝐺 ) ) |
| 5 | eqid | ⊢ ( Base ‘ 𝐺 ) = ( Base ‘ 𝐺 ) | |
| 6 | 5 3 | cntrval | ⊢ ( ( Cntz ‘ 𝐺 ) ‘ ( Base ‘ 𝐺 ) ) = ( Cntr ‘ 𝐺 ) |
| 7 | 6 2 | eqtr4i | ⊢ ( ( Cntz ‘ 𝐺 ) ‘ ( Base ‘ 𝐺 ) ) = 𝑍 |
| 8 | 1 5 | oppgbas | ⊢ ( Base ‘ 𝐺 ) = ( Base ‘ 𝑂 ) |
| 9 | eqid | ⊢ ( Cntz ‘ 𝑂 ) = ( Cntz ‘ 𝑂 ) | |
| 10 | 8 9 | cntrval | ⊢ ( ( Cntz ‘ 𝑂 ) ‘ ( Base ‘ 𝐺 ) ) = ( Cntr ‘ 𝑂 ) |
| 11 | 4 7 10 | 3eqtr3i | ⊢ 𝑍 = ( Cntr ‘ 𝑂 ) |