5.1 Determinants Which Represent Particular Polynomials 173
φn=
1
(1−x)
n+1
∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣
∣
1 −xx
11 −x 0
1 /2! 1 1 −x 0
1 /3! 1 /2! 1 1 −x 0
.....................................................
1 /(n−1)! 1/(n−2)!.............. 11 −x 0
1 /n!1/(n−1)!.............. 1 /2! 1 0
∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣
∣
n+1
(5.1.8)
After expanding the determinant by the single nonzero element in the last
column, the theorem follows from (5.1.2) and (5.1.4).
Exercises
Prove that
1.
n
∑
r=0
αrx
n−r
y
r
=
∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣
α 0 α 1 α 2 α 3 ··· αn− 1 αn
−yx
−yx
−yx
.................
−yx
∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣
n+1
.
2.(x+y)
n
=
∣
∣
∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣
1 xx
2
x
3
··· x
n− 1
x
n
− 1 yxyx
2
y ··· x
n− 2
yx
n− 1
y
− 1 yxy··· x
n− 3
yx
n− 2
y
− 1 y ··· x
n− 4
yx
n− 3
y
...........................
− 1 y
∣
∣
∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣
n+1
.
3.(−b)
n
2 F 0
(
x
a
,−n;−
b
a
)
=
∣
∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣
−c 1 b
a −c 2 b
2 a −c 3 b
3 a −c 4
··· ··· ···
−cn− 1 b
(n−1)a −cn
∣
∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ n
,
where
cr=(r−1)a+b+x. (Frost and Sackfield)
and 2 F 0 is the generalized hypergeometric function.