let m be non empty Element of NAT ; for x, a being Element of REAL
for i being Element of NAT st 1 <= i & i <= m holds
(reproj i,(0* m)) . (a * x) = a * ((reproj i,(0* m)) . x)
let x, a be Element of REAL ; for i being Element of NAT st 1 <= i & i <= m holds
(reproj i,(0* m)) . (a * x) = a * ((reproj i,(0* m)) . x)
let i be Element of NAT ; ( 1 <= i & i <= m implies (reproj i,(0* m)) . (a * x) = a * ((reproj i,(0* m)) . x) )
assume
( 1 <= i & i <= m )
; (reproj i,(0* m)) . (a * x) = a * ((reproj i,(0* m)) . x)
then A1:
Replace (0* m),i,(a * x) = a * (Replace (0* m),i,x)
by Th10;
Replace (0* m),i,x = (reproj i,(0* m)) . x
by PDIFF_1:def 5;
hence
(reproj i,(0* m)) . (a * x) = a * ((reproj i,(0* m)) . x)
by A1, PDIFF_1:def 5; verum