Metamath Proof Explorer


Theorem bcs3

Description: Corollary of the Bunjakovaskij-Cauchy-Schwarz inequality bcsiHIL . (Contributed by NM, 26-May-2006) (New usage is discouraged.)

Ref Expression
Assertion bcs3 A B norm B 1 A ih B norm A

Proof

Step Hyp Ref Expression
1 abshicom A B A ih B = B ih A
2 1 3adant3 A B norm B 1 A ih B = B ih A
3 bcs2 B A norm B 1 B ih A norm A
4 3 3com12 A B norm B 1 B ih A norm A
5 2 4 eqbrtrd A B norm B 1 A ih B norm A