## 7 Arithmetic Functions

This chapter describes the Calc commands for doing simple calculations
on numbers, such as addition, absolute value, and square roots. These
commands work by removing the top one or two values from the stack,
performing the desired operation, and pushing the result back onto the
stack. If the operation cannot be performed, the result pushed is a
formula instead of a number, such as ‘`2/0`’ (because division by zero
is invalid) or ‘`sqrt(x)`’ (because the argument ‘`x`’ is a formula).

Most of the commands described here can be invoked by a single keystroke.
Some of the more obscure ones are two-letter sequences beginning with
the `f` (“functions”) prefix key.

See Numeric Prefix Arguments, for a discussion of the effect of numeric
prefix arguments on commands in this chapter which do not otherwise
interpret a prefix argument.