Metamath Proof Explorer


Theorem marepveval

Description: An entry of a matrix with a replaced column. (Contributed by AV, 14-Feb-2019) (Revised by AV, 26-Feb-2019)

Ref Expression
Hypotheses marepvfval.a A = N Mat R
marepvfval.b B = Base A
marepvfval.q Q = N matRepV R
marepvfval.v V = Base R N
Assertion marepveval M B C V K N I N J N I M Q C K J = if J = K C I I M J

Proof

Step Hyp Ref Expression
1 marepvfval.a A = N Mat R
2 marepvfval.b B = Base A
3 marepvfval.q Q = N matRepV R
4 marepvfval.v V = Base R N
5 1 2 3 4 marepvval M B C V K N M Q C K = i N , j N if j = K C i i M j
6 5 adantr M B C V K N I N J N M Q C K = i N , j N if j = K C i i M j
7 simprl M B C V K N I N J N I N
8 simplrr M B C V K N I N J N i = I J N
9 fvexd M B C V K N I N J N C i V
10 ovexd M B C V K N I N J N i M j V
11 9 10 ifcld M B C V K N I N J N if j = K C i i M j V
12 11 adantr M B C V K N I N J N i = I j = J if j = K C i i M j V
13 eqeq1 j = J j = K J = K
14 13 adantl i = I j = J j = K J = K
15 fveq2 i = I C i = C I
16 15 adantr i = I j = J C i = C I
17 oveq12 i = I j = J i M j = I M J
18 14 16 17 ifbieq12d i = I j = J if j = K C i i M j = if J = K C I I M J
19 18 adantl M B C V K N I N J N i = I j = J if j = K C i i M j = if J = K C I I M J
20 7 8 12 19 ovmpodv2 M B C V K N I N J N M Q C K = i N , j N if j = K C i i M j I M Q C K J = if J = K C I I M J
21 6 20 mpd M B C V K N I N J N I M Q C K J = if J = K C I I M J