let a1, a2, a3, a4, a5, b1, b2, b3, b4, b5 be Real; ( ( for x being Real holds Polynom (a1,a2,a3,a4,a5,x) = Polynom (b1,b2,b3,b4,b5,x) ) implies ( a1 - b1 = b3 - a3 & a2 - b2 = b4 - a4 ) )
assume
for x being Real holds Polynom (a1,a2,a3,a4,a5,x) = Polynom (b1,b2,b3,b4,b5,x)
; ( a1 - b1 = b3 - a3 & a2 - b2 = b4 - a4 )
then
( ((a1 - a2) + a3) - a4 = ((b1 - b2) + b3) - b4 & ((a1 + a2) + a3) + a4 = ((b1 + b2) + b3) + b4 )
by Th7;
hence
( a1 - b1 = b3 - a3 & a2 - b2 = b4 - a4 )
; verum