`(- z[1] z[2])`procedure`-``z`procedure`(- z[1] z[2] ...)`procedure`(/ z[1] z[2])`procedure`/``z`procedure`(/ z[1] z[2] ...)`procedureWith two or more arguments, these procedures return the difference or quotient of their arguments, associating to the left. With one argument, however, they return the additive or multiplicative inverse of their argument.

(- 3 4) ===> -1 (- 3 4 5) ===> -6 (- 3) ===> -3 (/ 3 4 5) ===> 3/20 (/ 3) ===> 1/3