7.9 Exercises 223
Section 7.5
Examine the following series for convergence by
Comparison test (useln 1 n 1 < 1 n): 46. 47.
D’Alembert ratio test: 48. 49.
Cauchy integral test: 50. 51.
Section 7.6
Find the radius of convergence of each of the following series:
Write down the first 5 terms of the MacLaurin series of the following functions:
58.(1 1 + 1 x)
123
- 60.(1 1 − 1 x)
− 122
62.sin 12 x
2
- 64.e
− 3 x
66.A body with rest mass m
0
and speed vhas relativistic energy
and kinetic energyT 1 = 1 E 1 − 1 m
0
c
2
. Express Tas a power series in vand show that the series
reduces to the nonrelativistic kinetic energy in the limitv 2 c 1 → 10.
67.The equation of state of a gas can be expressed in terms of the series
where theB
i
are called virial coefficients. Find the first three coefficients for
(i)the van der Waals equation,
(ii)the Dieterici equation,
(i)Expand each of the following functions as a Taylor series about the given point, and
(ii)find the values of x for which the series converges:
- 69.e
x
, 2 70.sin 1 x, π 22 71.ln 1 x, 2
1
1
x
,
p V nb nRTe
an RTV
()−=
−
p
na
V
- Vnb nRT
−=
2
2
()
pV nRT B T
n
V
i
i
i
=
=
∑
0
∞
()
Emc
mc
c
==
−/
2 0
2
22
1 v
e
x
x
2
− 1
ln( ) 12 2
2
−+xx
x
1
3 +x
1
1
2
+x
n
nn
n
x
=
∑
−
0
2
1
3
∞
()
m
mm
mx
=
∑
1
∞
n
n
x
n
=
∑
1
2
∞
n
n
nx
=
∑
1
∞
r
rr
x
=
∑
−
0
2
1
∞
()
m
m
m
x
=
∑
0
4
∞
n
nn
=
∑
2
1
∞
ln
r
a
r
=
∑
1
1
∞
r
a
r
=
∑
1
1
∞
s
a
s
s
=
∑
0
1
∞
()!
r
r
r
=
∑
1
3
∞
ln
n
n
=
∑
2
1
∞
ln