Exactly, it is important and courteous still to cite your resources and tools.
I find a good workaround is to just say "some very quick research of my own leads me to ...", and then summarize what ChatGPT said. Especially if you are using e.g. an LLM with search enabled, this is borderline almost literally true, but makes it clear you aren't just stating something completely on your own.
Of course, you should still actually verify the outputs. If you do, there is not much wrong with not mentioning using the LLM, since you've don't the most important thing anyway (not be lazy in your response). If you don't verify, you had better say that.
I find a good workaround is to just say "some very quick research of my own leads me to ...", and then summarize what ChatGPT said. Especially if you are using e.g. an LLM with search enabled, this is borderline almost literally true, but makes it clear you aren't just stating something completely on your own.
Of course, you should still actually verify the outputs. If you do, there is not much wrong with not mentioning using the LLM, since you've don't the most important thing anyway (not be lazy in your response). If you don't verify, you had better say that.