Metamath Proof Explorer


Definition df-unit

Description: Define the set of units in a ring, that is, all elements with a left and right multiplicative inverse. (Contributed by Mario Carneiro, 1-Dec-2014)

Ref Expression
Assertion df-unit Unit = ( 𝑤 ∈ V ↦ ( ( ( ∥r𝑤 ) ∩ ( ∥r ‘ ( oppr𝑤 ) ) ) “ { ( 1r𝑤 ) } ) )

Detailed syntax breakdown

Step Hyp Ref Expression
0 cui Unit
1 vw 𝑤
2 cvv V
3 cdsr r
4 1 cv 𝑤
5 4 3 cfv ( ∥r𝑤 )
6 coppr oppr
7 4 6 cfv ( oppr𝑤 )
8 7 3 cfv ( ∥r ‘ ( oppr𝑤 ) )
9 5 8 cin ( ( ∥r𝑤 ) ∩ ( ∥r ‘ ( oppr𝑤 ) ) )
10 9 ccnv ( ( ∥r𝑤 ) ∩ ( ∥r ‘ ( oppr𝑤 ) ) )
11 cur 1r
12 4 11 cfv ( 1r𝑤 )
13 12 csn { ( 1r𝑤 ) }
14 10 13 cima ( ( ( ∥r𝑤 ) ∩ ( ∥r ‘ ( oppr𝑤 ) ) ) “ { ( 1r𝑤 ) } )
15 1 2 14 cmpt ( 𝑤 ∈ V ↦ ( ( ( ∥r𝑤 ) ∩ ( ∥r ‘ ( oppr𝑤 ) ) ) “ { ( 1r𝑤 ) } ) )
16 0 15 wceq Unit = ( 𝑤 ∈ V ↦ ( ( ( ∥r𝑤 ) ∩ ( ∥r ‘ ( oppr𝑤 ) ) ) “ { ( 1r𝑤 ) } ) )