You can probably start with "Deep Learning" by Ian Goodfellow, Yoshua Bengio and Aaron Courville (MIT Press).
HTML version:
https://www.deeplearningbook.org/
Physical version:
https://www.amazon.com/Deep-Learning-Adaptive-Computation-Machine/dp/0262035618/ref=sr_1_1?ie=UTF8&qid=1472485235&sr=8-1&keywords=deep+learning+book
The second book that related to AI might be:
https://www.amazon.com/Pattern-Recognition-Learning-Information-Statistics/dp/0387310738/ref=pd_aw_sim_sccl_2/136-4531799-6549820?psc=1&pf_rd_p=8823fd67-e420-4b8a-b095-6431562fffa4&pf_rd_r=FRCDRACHFPHCAFZX40R1&pd_rd_wg=5H7I4&pd_rd_w=mNGs3&content-id=amzn1.sym.8823fd67-e420-4b8a-b095-6431562fffa4&pd_rd_r=0636683c-9674-48fd-8037-eacdb2011fc6&pd_rd_i=0387310738&psc=1
Those two books are quite often become main lecture material in University teaching introduction of AI/DL/ML courses.
#machinelearning #deeplearning