import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D
 
# Define the function
def f(x, y):
    return 9 - 2*x + 4*y - x**2 - 4*y**2
 
# Generate x and y values
x = np.linspace(-5, 5, 100)
y = np.linspace(-5, 5, 100)
X, Y = np.meshgrid(x, y)
Z = f(X, Y)
 
# Create 3D plot
fig = plt.figure()
ax = fig.add_subplot(111, projection='3d')
ax.plot_surface(X, Y, Z, cmap='viridis')
 
# Set labels
ax.set_xlabel('x')
ax.set_ylabel('y')
ax.set_zlabel('f(x, y)')
 
# Show plot
plt.show()

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