Metamath Proof Explorer


Theorem stoweidlem10

Description: Lemma for stoweid . This lemma is used by Lemma 1 in BrosowskiDeutsh p. 90, this lemma is an application of Bernoulli's inequality. (Contributed by Glauco Siliprandi, 20-Apr-2017)

Ref Expression
Assertion stoweidlem10
|- ( ( A e. RR /\ N e. NN0 /\ A <_ 1 ) -> ( 1 - ( N x. A ) ) <_ ( ( 1 - A ) ^ N ) )

Proof

Step Hyp Ref Expression
1 renegcl
 |-  ( A e. RR -> -u A e. RR )
2 1 3ad2ant1
 |-  ( ( A e. RR /\ N e. NN0 /\ A <_ 1 ) -> -u A e. RR )
3 simp2
 |-  ( ( A e. RR /\ N e. NN0 /\ A <_ 1 ) -> N e. NN0 )
4 simpr
 |-  ( ( A e. RR /\ A <_ 1 ) -> A <_ 1 )
5 simpl
 |-  ( ( A e. RR /\ A <_ 1 ) -> A e. RR )
6 1red
 |-  ( ( A e. RR /\ A <_ 1 ) -> 1 e. RR )
7 5 6 lenegd
 |-  ( ( A e. RR /\ A <_ 1 ) -> ( A <_ 1 <-> -u 1 <_ -u A ) )
8 4 7 mpbid
 |-  ( ( A e. RR /\ A <_ 1 ) -> -u 1 <_ -u A )
9 8 3adant2
 |-  ( ( A e. RR /\ N e. NN0 /\ A <_ 1 ) -> -u 1 <_ -u A )
10 bernneq
 |-  ( ( -u A e. RR /\ N e. NN0 /\ -u 1 <_ -u A ) -> ( 1 + ( -u A x. N ) ) <_ ( ( 1 + -u A ) ^ N ) )
11 2 3 9 10 syl3anc
 |-  ( ( A e. RR /\ N e. NN0 /\ A <_ 1 ) -> ( 1 + ( -u A x. N ) ) <_ ( ( 1 + -u A ) ^ N ) )
12 recn
 |-  ( A e. RR -> A e. CC )
13 12 3ad2ant1
 |-  ( ( A e. RR /\ N e. NN0 /\ A <_ 1 ) -> A e. CC )
14 nn0cn
 |-  ( N e. NN0 -> N e. CC )
15 14 3ad2ant2
 |-  ( ( A e. RR /\ N e. NN0 /\ A <_ 1 ) -> N e. CC )
16 1cnd
 |-  ( ( A e. RR /\ N e. NN0 /\ A <_ 1 ) -> 1 e. CC )
17 mulneg1
 |-  ( ( A e. CC /\ N e. CC ) -> ( -u A x. N ) = -u ( A x. N ) )
18 17 oveq2d
 |-  ( ( A e. CC /\ N e. CC ) -> ( 1 + ( -u A x. N ) ) = ( 1 + -u ( A x. N ) ) )
19 18 3adant3
 |-  ( ( A e. CC /\ N e. CC /\ 1 e. CC ) -> ( 1 + ( -u A x. N ) ) = ( 1 + -u ( A x. N ) ) )
20 simp3
 |-  ( ( A e. CC /\ N e. CC /\ 1 e. CC ) -> 1 e. CC )
21 mulcl
 |-  ( ( A e. CC /\ N e. CC ) -> ( A x. N ) e. CC )
22 21 3adant3
 |-  ( ( A e. CC /\ N e. CC /\ 1 e. CC ) -> ( A x. N ) e. CC )
23 20 22 negsubd
 |-  ( ( A e. CC /\ N e. CC /\ 1 e. CC ) -> ( 1 + -u ( A x. N ) ) = ( 1 - ( A x. N ) ) )
24 mulcom
 |-  ( ( A e. CC /\ N e. CC ) -> ( A x. N ) = ( N x. A ) )
25 24 oveq2d
 |-  ( ( A e. CC /\ N e. CC ) -> ( 1 - ( A x. N ) ) = ( 1 - ( N x. A ) ) )
26 25 3adant3
 |-  ( ( A e. CC /\ N e. CC /\ 1 e. CC ) -> ( 1 - ( A x. N ) ) = ( 1 - ( N x. A ) ) )
27 19 23 26 3eqtrd
 |-  ( ( A e. CC /\ N e. CC /\ 1 e. CC ) -> ( 1 + ( -u A x. N ) ) = ( 1 - ( N x. A ) ) )
28 13 15 16 27 syl3anc
 |-  ( ( A e. RR /\ N e. NN0 /\ A <_ 1 ) -> ( 1 + ( -u A x. N ) ) = ( 1 - ( N x. A ) ) )
29 1cnd
 |-  ( A e. RR -> 1 e. CC )
30 29 12 negsubd
 |-  ( A e. RR -> ( 1 + -u A ) = ( 1 - A ) )
31 30 oveq1d
 |-  ( A e. RR -> ( ( 1 + -u A ) ^ N ) = ( ( 1 - A ) ^ N ) )
32 31 3ad2ant1
 |-  ( ( A e. RR /\ N e. NN0 /\ A <_ 1 ) -> ( ( 1 + -u A ) ^ N ) = ( ( 1 - A ) ^ N ) )
33 11 28 32 3brtr3d
 |-  ( ( A e. RR /\ N e. NN0 /\ A <_ 1 ) -> ( 1 - ( N x. A ) ) <_ ( ( 1 - A ) ^ N ) )