theorem Th47:
for
K being
Field for
n,
i0 being
Element of
NAT for
A being
Matrix of
n,
K st 1
<= i0 &
i0 <= n &
i0 <> 1 & ( for
i,
j being
Nat st 1
<= i &
i <= n & 1
<= j &
j <= n holds
( (
i = 1 &
j = i0 implies
A * (
i,
j)
= 1. K ) & (
i = i0 &
j = 1 implies
A * (
i,
j)
= 1. K ) & (
i = 1 &
j = 1 implies
A * (
i,
j)
= 0. K ) & (
i = i0 &
j = i0 implies
A * (
i,
j)
= 0. K ) & ( ( ( not
i = 1 & not
i = i0 ) or ( not
j = 1 & not
j = i0 ) ) implies ( (
i = j implies
A * (
i,
j)
= 1. K ) & (
i <> j implies
A * (
i,
j)
= 0. K ) ) ) ) ) holds
A = SwapDiagonal (
K,
n,
i0)