Note that square brackets are a concatentation operator (not a list operator like in some other langauges), so your examples are just complicated ways of writing character vectors. For example, this code:
Course1 = ['A','B','C','E','F','G','I','P','Q'];
is just a longer way of writing this equivalent character vector:
Course1 = 'ABCEFGIPQ';
The same applies to your requested outputs, e.g. this:
['A', 'B', 'C', 'E', 'F', 'G', 'H', 'I', 'K', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'Z']
is exactly equivalent to this simple character vector:
'ABCEFGHIKPQRSTUVZ'
And that is already what UNION and INTERSECT are giving you: character vectors which consist of lots of individual characters. Understanding what square brackets actually do, and what character vectors are, is very important when using MATLAB:
