import pandas as pd

# create sample DataFrame
data = {'A': [1, 2, 3], 'B': [4, 5, 6], 'C': [7, 8, 9]}
df = pd.DataFrame(data)

# normalize DataFrame using apply and lambda function
df_normalized = df.apply(lambda x: (x - x.min()) / (x.max() - x.min()))
print(df_normalized)