TITLE: How do you integrate imaginary numbers?
QUESTION [13 upvotes]: How would you find, for instance, $\int_0^4 i\> x \,dx$?  Can you just treat $i$ as a constant, or do you have to do something more sophisticated?
Thanks!

REPLY [5 votes]: "i" has one an only value , it never changes, hence it can be just taken out as constant.
$$\int i x \,dx = i\int x \,dx$$