Metamath Proof Explorer


Theorem cnnvs

Description: The scalar product operation of the normed complex vector space of complex numbers. (Contributed by NM, 12-Jan-2008) (New usage is discouraged.)

Ref Expression
Hypothesis cnnvs.6 U = + × abs
Assertion cnnvs × = 𝑠OLD U

Proof

Step Hyp Ref Expression
1 cnnvs.6 U = + × abs
2 eqid 𝑠OLD U = 𝑠OLD U
3 2 smfval 𝑠OLD U = 2 nd 1 st U
4 1 fveq2i 1 st U = 1 st + × abs
5 opex + × V
6 absf abs :
7 cnex V
8 fex abs : V abs V
9 6 7 8 mp2an abs V
10 5 9 op1st 1 st + × abs = + ×
11 4 10 eqtri 1 st U = + ×
12 11 fveq2i 2 nd 1 st U = 2 nd + ×
13 addex + V
14 mulex × V
15 13 14 op2nd 2 nd + × = ×
16 3 12 15 3eqtrri × = 𝑠OLD U