Integrals with Exponentials
(58)
Z
e
ax
dx =
1
a
e
ax
(59)
Z
√
xe
ax
dx =
1
a
√
xe
ax
+
i
√
π
2a
3/2
erf
(
i
√
ax
)
, where erf(x)=
2
√
π
Z
x
0
e
-t
2
dt
(60)
Z
xe
x
dx =(x - 1)e
x
(61)
Z
xe
ax
dx =
x
a
-
1
a
2
e
ax
(62)
Z
x
2
e
x
dx =
(
x
2
- 2x +2
)
e
x
(63)
Z
x
2
e
ax
dx =
x
2
a
-
2x
a
2
+
2
a
3
e
ax
(64)
Z
x
3
e
x
dx =
(
x
3
- 3x
2
+6x - 6
)
e
x
(65)
Z
x
n
e
ax
dx =
x
n
e
ax
a
-
n
a
Z
x
n-1
e
ax
dx
(66)
Z
x
n
e
ax
dx =
(-1)
n
a
n+1
Γ[1 + n, -ax], where Γ(a, x)=
Z
∞
x
t
a-1
e
-t
dt
(67)
Z
e
ax
2
dx = -
i
√
π
2
√
a
erf
(
ix
√
a
)
7