Theorem comorr2 445

Description: Commutation law.

Assertion

Ref	Expression
comorr2	b C (a ∪ b)

Proof of Theorem comorr2

Step	Hyp	Ref	Expression
1		comor2 444	. 2 (a ∪ b) C b
2	1	comcom 435	1 b C (a ∪ b)

Syntax hints:   C wc 3   ∪ wo 6

This theorem is referenced by:  ud3lem1c 550  u4lemanb 600  u4lemob 615  u4lemc1 665  u4lem5 746  u4lem6 750  u3lem13b 772  3vth9 794  2oath1 808

This theorem was proved from axioms:  ax-a1 29  ax-a2 30  ax-a3 31  ax-a5 33  ax-r1 34  ax-r2 35  ax-r4 36  ax-r5 37  ax-r3 421

This theorem depends on definitions:  df-b 38  df-a 39  df-t 40  df-f 41  df-le1 122  df-le2 123  df-c1 124  df-c2 125

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