Metamath Proof Explorer


Theorem intpreima

Description: Preimage of an intersection. (Contributed by FL, 28-Apr-2012)

Ref Expression
Assertion intpreima FunFAF-1A=xAF-1x

Proof

Step Hyp Ref Expression
1 intiin A=xAx
2 1 imaeq2i F-1A=F-1xAx
3 iinpreima FunFAF-1xAx=xAF-1x
4 2 3 eqtrid FunFAF-1A=xAF-1x