### 7.4 Arithmetic Operators

The arithmetic operators take numeric operands and produce numeric results.

a`+` b
  Yields the sum of a and b.

a`-` b
  Subtracts b from a and yields the difference.

a`*` b
  Yields the product of a and b. If either a or b is 0, then the result is 0, even if the other operand is missing.

a`/` b
  Divides a by b and yields the quotient. If a is 0, then the result is 0, even if b is missing. If b is zero, the result is system-missing.

a`**` b
  Yields the result of raising a to the power b. If a is negative and b is not an integer, the result is system-missing. The result of `0**0` is system-missing as well.

`-` a
  Reverses the sign of a.