theorem Th14: :: MATRIX12:14

for l, n being Nat
for K being Field
for a being Element of K st l in dom (1. (K,n)) & a <> 0. K holds
( SXLine ((1. (K,n)),l,a) is invertible & (SXLine ((1. (K,n)),l,a)) ~ = SXLine ((1. (K,n)),l,(a ")) )