163k views
0 votes
Consider the function f(z) = z, where z E C. a). Use the epsilon to delta definition of limit to show that f is continuous for all z = z₀. We will now show that g(z) = zⁿ is continuous at z = z₀ using the method of induction. First, we establish a base case for n=1. That is, we demonstrate that the function f(z) = z is continuous at z = z₀ (notice that this was accomplished in part (a)).

User Dscarr
by
8.3k points

1 Answer

3 votes

Final Answer

Yes, the function
\( f(z) = z \) is continuous for all \( z = z_0 \).

Step-by-step explanation

In the epsilon-delta definition of continuity, we aim to show that for any given epsilon (ε), there exists a delta (δ) such that whenever
\( |z - z_0| < \delta \), it implies \( |f(z) - f(z_0)| < \epsilon \). For the function \
( f(z) = z \), when
\( z = z_0 \), \( |f(z) - f(z_0)| = |z - z_0| \). Therefore, choosing
\( \delta = \epsilon \) suffices, as it ensures that \( |z - z_0| < \delta \) implies \( |z - z_0| < \epsilon \). Hence, the function \( f(z) = z \) is continuous at any point \( z = z_0 \).

Now, for the induction step, let's consider the function
\( g(z) = z^n \)where \( n = 1 \) is our base case. We've established in part (a) that f(z) = z is continuous, which serves as the base case for \( n = 1 \). Now, we need to show that if
\( g(z) = z^n \) is continuous at \( z = z_0 \), then
\( g(z) = z^(n+1) \)is also continuous at
\( z = z_0 \). This proof involves using the continuity of
\( g(z) \) to show the continuity of
\( g(z) \) raised to the power of
\( n+1 \).

User Thomas Uhrig
by
8.2k points