Metamath Proof Explorer


Theorem shftcan2

Description: Cancellation law for the shift operation. (Contributed by NM, 4-Aug-2005) (Revised by Mario Carneiro, 5-Nov-2013)

Ref Expression
Hypothesis shftfval.1 FV
Assertion shftcan2 ABFshiftAshiftAB=FB

Proof

Step Hyp Ref Expression
1 shftfval.1 FV
2 negneg AA=A
3 2 adantr ABA=A
4 3 oveq2d ABFshiftAshiftA=FshiftAshiftA
5 4 fveq1d ABFshiftAshiftAB=FshiftAshiftAB
6 negcl AA
7 1 shftcan1 ABFshiftAshiftAB=FB
8 6 7 sylan ABFshiftAshiftAB=FB
9 5 8 eqtr3d ABFshiftAshiftAB=FB