Metamath Proof Explorer


Theorem bcs2

Description: Corollary of the Bunjakovaskij-Cauchy-Schwarz inequality bcsiHIL . (Contributed by NM, 24-May-2006) (New usage is discouraged.)

Ref Expression
Assertion bcs2 ABnormA1AihBnormB

Proof

Step Hyp Ref Expression
1 hicl ABAihB
2 1 abscld ABAihB
3 2 3adant3 ABnormA1AihB
4 normcl AnormA
5 normcl BnormB
6 remulcl normAnormBnormAnormB
7 4 5 6 syl2an ABnormAnormB
8 7 3adant3 ABnormA1normAnormB
9 5 3ad2ant2 ABnormA1normB
10 bcs ABAihBnormAnormB
11 10 3adant3 ABnormA1AihBnormAnormB
12 4 3ad2ant1 ABnormA1normA
13 normge0 B0normB
14 13 3ad2ant2 ABnormA10normB
15 9 14 jca ABnormA1normB0normB
16 simp3 ABnormA1normA1
17 1re 1
18 lemul1a normA1normB0normBnormA1normAnormB1normB
19 17 18 mp3anl2 normAnormB0normBnormA1normAnormB1normB
20 12 15 16 19 syl21anc ABnormA1normAnormB1normB
21 5 recnd BnormB
22 21 mulid2d B1normB=normB
23 22 3ad2ant2 ABnormA11normB=normB
24 20 23 breqtrd ABnormA1normAnormBnormB
25 3 8 9 11 24 letrd ABnormA1AihBnormB