I need to know the important of Discrete Mathematics in Artificial Intelligence.
Discrete mathematics will help you to understand fundamental structures in mathematics while all the while training you to develop logic intuitions (writing proofs of induction, introducing you to techniques like the pigeon-hole principle). To go into Artificial Intelligence there really isn't a straight forward path as AI as an umbrella has widened so much since the term was coined but people just decided to stick to it because it made sense to call every sub discipline -- Machine learning, Decision making, NLP, Question answering, Info retrieval -- as AI.
Once you have a strong grounding in writng proofs and understanding logic you can get started with specific areas by diving into the latest research. If not, you have to strengthen your foundations by working on a discrete mathematics course perhaps.In this way,Discrete mathematics will help you in Artificial Intelligence.