Unsolicited Math Textbooks Redesign

Partly for fun, partly as a quick school assignment and partly just because, I did these new concept covers for the as-of-now-undistinguishable-from-each-other math textbook series.

There are definitely worse designed textbook covers around than the originals, but when in high school we would get these mixed up all the time and never brought the right one to school. Luckily the only math I need to do these days Sketch does for me :)