let a, a9, b, b9, c, c9, d, d9 be Real; ( ( for x being Real holds Polynom (a,b,c,d,x) = Polynom (a9,b9,c9,d9,x) ) implies ( a = a9 & b = b9 & c = c9 & d = d9 ) )
(- 1) |^ 3 =
- (1 |^ (2 + 1))
by Lm1, POWER:2
.=
- ((1 |^ 2) * 1)
;
then A1:
( 0 |^ 3 = 0 & (- 1) |^ 3 = - 1 )
by NEWTON:11;
A2: 2 |^ 3 =
2 |^ (2 + 1)
.=
(2 |^ (1 + 1)) * 2
by NEWTON:6
.=
((2 |^ 1) * 2) * 2
by NEWTON:6
.=
(2 |^ 1) * (2 * 2)
;
assume A3:
for x being Real holds Polynom (a,b,c,d,x) = Polynom (a9,b9,c9,d9,x)
; ( a = a9 & b = b9 & c = c9 & d = d9 )
then A4:
Polynom (a,b,c,d,2) = Polynom (a9,b9,c9,d9,2)
;
Polynom (a,b,c,d,1) = Polynom (a9,b9,c9,d9,1)
by A3;
then
(((a * 1) + (b * 1)) + (c * 1)) + d = Polynom (a9,b9,c9,d9,1)
;
then A5: ((a + b) + c) + d =
(((a9 * 1) + (b9 * 1)) + (c9 * 1)) + d9
.=
((a9 + b9) + c9) + d9
;
( Polynom (a,b,c,d,0) = Polynom (a9,b9,c9,d9,0) & Polynom (a,b,c,d,(- 1)) = Polynom (a9,b9,c9,d9,(- 1)) )
by A3;
hence
( a = a9 & b = b9 & c = c9 & d = d9 )
by A5, A1, A4, A2; verum