Description: In a nonzero ring, the mapping of the index set of a free module onto the unit vectors of the free module is a 1-1 onto function. (Contributed by AV, 10-Mar-2019)
Ref | Expression | ||
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Hypothesis | uvcf1o.u | |- U = ( R unitVec I ) |
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Assertion | uvcf1o | |- ( ( R e. NzRing /\ I e. W ) -> U : I -1-1-onto-> ran U ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | uvcf1o.u | |- U = ( R unitVec I ) |
|
2 | eqid | |- ( R freeLMod I ) = ( R freeLMod I ) |
|
3 | eqid | |- ( Base ` ( R freeLMod I ) ) = ( Base ` ( R freeLMod I ) ) |
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4 | 1 2 3 | uvcf1 | |- ( ( R e. NzRing /\ I e. W ) -> U : I -1-1-> ( Base ` ( R freeLMod I ) ) ) |
5 | f1f1orn | |- ( U : I -1-1-> ( Base ` ( R freeLMod I ) ) -> U : I -1-1-onto-> ran U ) |
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6 | 4 5 | syl | |- ( ( R e. NzRing /\ I e. W ) -> U : I -1-1-onto-> ran U ) |