Chapter 3 465
Figure 2 Solution for Exercise 7, Section 3.3.
Figure 3 Solution for Exercise 9, Section 3.3.
- See Fig. 2.
- See Fig. 3.
- By the chain rule we calculate
∂u
∂x
=∂v
∂w
∂w
∂x
+∂v
∂z
∂z
∂x
=∂v
∂w
+∂v
∂z
,
∂^2 u
∂x^2
= ∂
∂w
(∂v
∂w
+∂v
∂z
)∂w
∂x
+ ∂
∂z
(∂v
∂w
+∂v
∂z
)∂z
∂x
=∂
(^2) v
∂w^2 +^2
∂^2 v
∂w∂z+
∂^2 v
∂z^2