Metamath Proof Explorer


Theorem volsuplem

Description: Lemma for volsup . (Contributed by Mario Carneiro, 4-Jul-2014)

Ref Expression
Assertion volsuplem nFnFn+1ABAFAFB

Proof

Step Hyp Ref Expression
1 fveq2 x=AFx=FA
2 1 sseq2d x=AFAFxFAFA
3 2 imbi2d x=AnFnFn+1AFAFxnFnFn+1AFAFA
4 fveq2 x=kFx=Fk
5 4 sseq2d x=kFAFxFAFk
6 5 imbi2d x=knFnFn+1AFAFxnFnFn+1AFAFk
7 fveq2 x=k+1Fx=Fk+1
8 7 sseq2d x=k+1FAFxFAFk+1
9 8 imbi2d x=k+1nFnFn+1AFAFxnFnFn+1AFAFk+1
10 fveq2 x=BFx=FB
11 10 sseq2d x=BFAFxFAFB
12 11 imbi2d x=BnFnFn+1AFAFxnFnFn+1AFAFB
13 ssid FAFA
14 13 2a1i AnFnFn+1AFAFA
15 eluznn AkAk
16 fveq2 n=kFn=Fk
17 fvoveq1 n=kFn+1=Fk+1
18 16 17 sseq12d n=kFnFn+1FkFk+1
19 18 rspccva nFnFn+1kFkFk+1
20 15 19 sylan2 nFnFn+1AkAFkFk+1
21 20 anassrs nFnFn+1AkAFkFk+1
22 sstr2 FAFkFkFk+1FAFk+1
23 21 22 syl5com nFnFn+1AkAFAFkFAFk+1
24 23 expcom kAnFnFn+1AFAFkFAFk+1
25 24 a2d kAnFnFn+1AFAFknFnFn+1AFAFk+1
26 3 6 9 12 14 25 uzind4 BAnFnFn+1AFAFB
27 26 com12 nFnFn+1ABAFAFB
28 27 impr nFnFn+1ABAFAFB