A tip for the last one which actually makes it a lot easier is to instead of grouping the ones, group the zeroes and then inverse them. What you will get when grouping the zeroes is D A B' and inverted will be your answer of D' A' B following De Morgan laws
The trite answer is that K maps use Gray code rather than binary numerical order because it makes grouping possible (Yes! I just said "because it makes it work" - sorry). If you are interested there are lots of articles and posts on WHY this is the case, but you may need to dig around to understand the terminology. I like this post electronics.stackexchange.com/questions/161888/why-does-the-karnaugh-map-use-gray-code-and-not-binary :)KD
Does Kevin mean that each input value ONLY changes a bit at a time and not sequential 2-bit binary & is deliberately not used? E.g. 00, 01, 11, 10 and not 00, 01, 10, 11
If it is an 'and' operation between variables, then I think it doesn't matter whether I write AB or BA ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-YJSqf_Z024w.html
