Did Obama say lmfao in the union state address speech?

He did not. First, I think you are referring to the "State of the Union" address. This is a formal speech, and every president must deliver one to congress. There is no evidence that President Obama ever used internet slang like 'lmao" or the more vulgar "lmfao" during such a major speech as the State of the Union address. Further, the transcripts of his State of the Union speeches do not show that he ever said this.