... it. I planned it that way.
17 05
36 .5 Solutions
Solution 36.1
For y = −1, the equation is parabolic. For this case it is already in the canonical form, u
xx
= 0.
For y = −1, the equation is elliptic. ... we determine x and y in terms of ξ and ψ.
x = −
3
4
(ξ + ψ)
1/3
, y =
ψ −ξ
2
We calculate the derivatives of ξ and ψ.
ξ
x
=
√
−x =
3
4
(ξ + ψ)
1/6
, ξ
y
= −1
ψ
x
=...
... of
4
3
√
π
cm and a height of
4
3
√
π
.
106
a
x x
x
x
x
x∆
1
2
3
i
n-2
n-1
b
f( )
ξ
1
Figure 4. 2: Divide -and- Conquer Strategy for Approximating a Definite Integral.
4. 2.2 Properties
Linearity and ... [−1, 1] and −1 ≤ cos(x
0
) ≤ 1, the approximation
sin x ≈ x −
x
3
6
+
x
5
120
has a maximum error of
1
50 40
≈ 0.000198. Using this polynomial to approximate sin(1),
1 −
1
3...
... a to b and n is a unit vector that is orthogonal to a and b and in the direction s uch that
the ordered triple of vectors a, b and n form a right-handed system.
29
a
b
b
θ
b
Figure 2. 14: The ... from (1, 1) to
(4, 2) and the vector from (1, 1) to (2, 3). The second triangle is defined by the vector from (3, 7) to (4, 2) and the
vector from (3, 7) to (2, 3). (See Figure 2. 15. ) T...
... Z
z =
4m
1 + 4n
, m, n ∈ Z
There are an infinite set of rational numbers for which ı
z
has 1 as one of its values. For example,
ı
4 /5
= 1
1 /5
=
1,
e
ı2π /5
,
e
4 /5
,
e
ı6π /5
,
e
ı8π /5
7.8 ... cuts and define a branch so that z = 4 does not lie on a cut, and such that w = ı6 when z = 4.
Hint, Solution
Exercise 7. 24
Give the number of branches and locations of th...
... =
1
r
∂
∂r
r
∂u
∂r
+
1
r
2
∂
2
u
∂θ
2
= 0.
Therefore u is harmonic and is the real part of some analytic function.
Example 9.3.9 Find an analytic function f(z) whose real part is
u(r, θ) = r (log r cos θ −θ sin θ) .
44 7
The complex ... real and imaginary parts.
u
r
=
1
r
v
θ
, v
r
= −
1
r
u
θ
u
r
=
1
r
v
θ
, u
θ
= −rv
r
Solution 8. 15
Since w is analytic, u and v satisfy the...
... +
e
ıθ
n
ı
e
ıθ
dθ
=
(
ı2+
e
ıθ
)
n+1
n+1
2π
0
for n = −1
log
ı2 +
e
ıθ
2π
0
for n = −1
= 0
3. We parameterize the contour and do the integration.
z = r
e
ıθ
, r = 2 −sin
2
θ
4
, θ ∈ [0 . . . 4 )
48 7
Solution 10.6
C
f(z) ... a formula for writing the analytic function in terms
of its real part, u(r, θ). With the same method, we can find how to write...