Description: Multiplication is an operation on the complex numbers. This deprecated axiom is provided for historical compatibility but is not a bona fide axiom for complex numbers (independent of set theory) since it cannot be interpreted as a first-order or second-order statement (see https://us.metamath.org/downloads/schmidt-cnaxioms.pdf ). It may be deleted in the future and should be avoided for new theorems. Instead, the less specific ax-mulcl should be used. Note that uses of ax-mulf can be eliminated by using the defined operation ( x e. CC , y e. CC |-> ( x x. y ) ) in place of x. , from which this axiom (with the defined operation in place of x. ) follows as a theorem.
This axiom is justified by Theorem axmulf . (New usage is discouraged.) (Contributed by NM, 19-Oct-2004)
Ref | Expression | ||
---|---|---|---|
Assertion | ax-mulf | ⊢ · : ( ℂ × ℂ ) ⟶ ℂ |
Step | Hyp | Ref | Expression |
---|---|---|---|
0 | cmul | ⊢ · | |
1 | cc | ⊢ ℂ | |
2 | 1 1 | cxp | ⊢ ( ℂ × ℂ ) |
3 | 2 1 0 | wf | ⊢ · : ( ℂ × ℂ ) ⟶ ℂ |