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src/1_complex_numbers.md

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 ## Complex functions
 
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 Real functions can (most of the times) be written in terms of a Taylor series:
@@ -194,7 +194,7 @@ We see that during multiplication, the norm of the new number is the *product* o
 
 ## Differentiation and integration
 
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 We only consider differentiation and integration over *real* variables. We can then regard the complex ${\rm i}$ as another constant, and use our usual differentiation and integration rules: