set V = R ^* n;
now :: thesis: for a, b being Element of R
for x being Vector of (R ^* n) holds (a + b) * x = (a * x) + (b * x)
let a, b be Element of R; :: thesis: for x being Vector of (R ^* n) holds (a + b) * x = (a * x) + (b * x)
let x be Vector of (R ^* n); :: thesis: (a + b) * x = (a * x) + (b * x)
reconsider u = x as Element of n -tuples_on the carrier of R by DEF;
H1: a * x = the lmult of (R ^* n) . (a,u) by VECTSP_1:def 12
.= (vector_mult (n,R)) . (a,u) by DEF
.= a * u by Defm ;
H2: b * x = the lmult of (R ^* n) . (b,u) by VECTSP_1:def 12
.= (vector_mult (n,R)) . (b,u) by DEF
.= b * u by Defm ;
thus (a + b) * x = the lmult of (R ^* n) . ((a + b),u) by VECTSP_1:def 12
.= (vector_mult (n,R)) . ((a + b),u) by DEF
.= (a + b) * u by Defm
.= (a * u) + (b * u) by FVSUM_1:55
.= (vector_add (n,R)) . ((a * u),(b * u)) by Defa
.= (a * x) + (b * x) by H1, H2, DEF ; :: thesis: verum
end;
hence R ^* n is scalar-distributive by VECTSP_1:def 15; :: thesis: ( R ^* n is scalar-associative & R ^* n is vector-distributive )
now :: thesis: for a, b being Element of R
for x being Vector of (R ^* n) holds (a * b) * x = a * (b * x)
let a, b be Element of R; :: thesis: for x being Vector of (R ^* n) holds (a * b) * x = a * (b * x)
let x be Vector of (R ^* n); :: thesis: (a * b) * x = a * (b * x)
reconsider u = x as Element of n -tuples_on the carrier of R by DEF;
H: b * x = the lmult of (R ^* n) . (b,u) by VECTSP_1:def 12
.= (vector_mult (n,R)) . (b,u) by DEF
.= b * u by Defm ;
thus (a * b) * x = the lmult of (R ^* n) . ((a * b),u) by VECTSP_1:def 12
.= (vector_mult (n,R)) . ((a * b),u) by DEF
.= (a * b) * u by Defm
.= a * (b * u) by FVSUM_1:54
.= (vector_mult (n,R)) . (a,(b * u)) by Defm
.= the lmult of (R ^* n) . (a,(b * u)) by DEF
.= a * (b * x) by H, VECTSP_1:def 12 ; :: thesis: verum
end;
hence R ^* n is scalar-associative by VECTSP_1:def 16; :: thesis: R ^* n is vector-distributive
now :: thesis: for a being Element of R
for x, y being Vector of (R ^* n) holds a * (x + y) = (a * x) + (a * y)
let a be Element of R; :: thesis: for x, y being Vector of (R ^* n) holds a * (x + y) = (a * x) + (a * y)
let x, y be Vector of (R ^* n); :: thesis: a * (x + y) = (a * x) + (a * y)
reconsider u = x, v = y as Element of n -tuples_on the carrier of R by DEF;
H1: a * x = the lmult of (R ^* n) . (a,u) by VECTSP_1:def 12
.= (vector_mult (n,R)) . (a,u) by DEF
.= a * u by Defm ;
H2: a * y = the lmult of (R ^* n) . (a,v) by VECTSP_1:def 12
.= (vector_mult (n,R)) . (a,v) by DEF
.= a * v by Defm ;
x + y = (vector_add (n,R)) . (u,v) by DEF
.= u + v by Defa ;
hence a * (x + y) = the lmult of (R ^* n) . (a,(u + v)) by VECTSP_1:def 12
.= (vector_mult (n,R)) . (a,(u + v)) by DEF
.= a * (u + v) by Defm
.= (a * u) + (a * v) by FVSUM_1:56
.= (vector_add (n,R)) . ((a * u),(a * v)) by Defa
.= (a * x) + (a * y) by H1, H2, DEF ;
:: thesis: verum
end;
hence R ^* n is vector-distributive by VECTSP_1:def 14; :: thesis: verum