What is the font used for the cover of James Stewarts Calculus textbooks?
It’s even possible that it may be a custom-made font just for that book cover. Many times, a graphic designer will take a base font, convert it into individual vector drawings, and then alter it in various ways even to the point that it no longer directly resembles the original font. Or it may actually be a font that was created by the company’s designer that is directly type-able straight from the keyboard, and they are probably the only ones who actually have that font file.