Whole note they may occasionally be put under a different line (or ledger line) in more complicated polyphonic passages, or when two instruments or vocalists are written on one staff and one is temporarily silent. The whole note and whole rest may also be used in music of free rhythm, such as Anglican chant, to denote a whole measure, irrespective of the time of that measure. The whole rest can be used this way in almost all or all forms of music. The symbol is first found in music notation from the late thirteenth century . The whole note derives from the
Time value of money on time value, and provides a simple introduction before considering more complicated and less familiar situations. This exposition follows . The fundamental change that the differential equation perspective brings is that, rather than computing a "number" (the present value "now"), one computes a "function" (the present value now or at any point in "future"). This function may then be analyzed—how does its value change over time—or compared with other functions. Formally, the statement that "value decreases over time" is given by defining the linear differential operator formula_37 as: This states that values decreases (−) over time (∂) at the discount