let a be Real; for A being Matrix of REAL
for i2, j2 being Nat st [i2,j2] in Indices A holds
(a * A) * i2,j2 = a * (A * i2,j2)
let A be Matrix of REAL ; for i2, j2 being Nat st [i2,j2] in Indices A holds
(a * A) * i2,j2 = a * (A * i2,j2)
let i2, j2 be Nat; ( [i2,j2] in Indices A implies (a * A) * i2,j2 = a * (A * i2,j2) )
reconsider ea = a as Element of F_Real ;
assume
[i2,j2] in Indices A
; (a * A) * i2,j2 = a * (A * i2,j2)
then (MXF2MXR (ea * (MXR2MXF A))) * i2,j2 =
ea * ((MXR2MXF A) * i2,j2)
by MATRIX_3:def 5
.=
a * (A * i2,j2)
;
hence
(a * A) * i2,j2 = a * (A * i2,j2)
by Def7; verum