> Were this my source code, I'd probably put the (* 2 a) on the next line (properly indented) so it stood out as the divisor. And that's exactly how written ma

> Were this my source code, I'd probably put the (* 2 a) on the next line (properly indented) so it stood out as the divisor. And that's exactly how written math does it (big bar for division of complex terms). Infix code notation has an extra set of '() around the numerator and denominator which helps in this specific case.