For these exercises, you are strongly encouraged to work primarily with the course book, lecture notes, and your own reasoning. The main goal is not only to arrive at a correct answer, but to practice the thinking that leads to it. Struggling with a problem, organizing your thoughts, making mistakes, and correcting them are all important parts of learning. When you work through the exercises yourself, you develop a deeper understanding of the material, a better sense of what you have and have not yet understood, and a stronger ability to explain and apply ideas independently. This is much more valuable in the long run than obtaining a quick answer with external help. To achieve these goals, you don't need more than the course book, lecture notes, and your own reasoning!
What is not in the spirit of the assignment is using tools that do the thinking or writing for you — for example, generating solutions, explanations, summaries, or polished text that you then submit as your own work. That is the concern with AI-based tools and similar systems. So the basic principle is: you can use tools that assist with mechanical work, but that do not replace your understanding, reasoning, or writing.
When in doubt, ask yourself: is this tool just helping me compute something, or is it doing the intellectual work I am supposed to do myself?
Anyways, if you use AI tools you must highlight it!