Is there a good book that explains the features of electronics with math?
This is a funny question.  Here is a list of books that are mathy for various sub-domains of electronics.(Not saying best, just mathy)  Also, all the IEEE papers are pretty mathy.

Control systems:
Introductory:
Linear Systems and Signals (The Oxford Series in Electrical and Computer Engineering) [Hardcover]

More advanced:
Fundamentals of Linear State Space Systems (McGraw-Hill Series in Electrical Engineering) [Hardcover]
John S Bay

Solid state:
Introductory:
Semiconductor Physics And Devices Semiconductor Physics And Devices
Donald Neamen (Author)

E&amp;M
Elements of Electromagnetics (The Oxford Series in Electrical and Computer Engineering)
Matthew N. O. Sadiku