Metamath Proof Explorer


Theorem ipassi

Description: Associative law for inner product. Equation I2 of Ponnusamy p. 363. (Contributed by NM, 25-Aug-2007) (New usage is discouraged.)

Ref Expression
Hypotheses ip1i.1 X=BaseSetU
ip1i.2 G=+vU
ip1i.4 S=𝑠OLDU
ip1i.7 P=𝑖OLDU
ip1i.9 UCPreHilOLD
Assertion ipassi ABXCXASBPC=ABPC

Proof

Step Hyp Ref Expression
1 ip1i.1 X=BaseSetU
2 ip1i.2 G=+vU
3 ip1i.4 S=𝑠OLDU
4 ip1i.7 P=𝑖OLDU
5 ip1i.9 UCPreHilOLD
6 oveq2 B=ifBXB0vecUASB=ASifBXB0vecU
7 6 oveq1d B=ifBXB0vecUASBPC=ASifBXB0vecUPC
8 oveq1 B=ifBXB0vecUBPC=ifBXB0vecUPC
9 8 oveq2d B=ifBXB0vecUABPC=AifBXB0vecUPC
10 7 9 eqeq12d B=ifBXB0vecUASBPC=ABPCASifBXB0vecUPC=AifBXB0vecUPC
11 10 imbi2d B=ifBXB0vecUAASBPC=ABPCAASifBXB0vecUPC=AifBXB0vecUPC
12 oveq2 C=ifCXC0vecUASifBXB0vecUPC=ASifBXB0vecUPifCXC0vecU
13 oveq2 C=ifCXC0vecUifBXB0vecUPC=ifBXB0vecUPifCXC0vecU
14 13 oveq2d C=ifCXC0vecUAifBXB0vecUPC=AifBXB0vecUPifCXC0vecU
15 12 14 eqeq12d C=ifCXC0vecUASifBXB0vecUPC=AifBXB0vecUPCASifBXB0vecUPifCXC0vecU=AifBXB0vecUPifCXC0vecU
16 15 imbi2d C=ifCXC0vecUAASifBXB0vecUPC=AifBXB0vecUPCAASifBXB0vecUPifCXC0vecU=AifBXB0vecUPifCXC0vecU
17 eqid 0vecU=0vecU
18 1 17 5 elimph ifBXB0vecUX
19 1 17 5 elimph ifCXC0vecUX
20 1 2 3 4 5 18 19 ipasslem11 AASifBXB0vecUPifCXC0vecU=AifBXB0vecUPifCXC0vecU
21 11 16 20 dedth2h BXCXAASBPC=ABPC
22 21 com12 ABXCXASBPC=ABPC
23 22 3impib ABXCXASBPC=ABPC