# A variable

variable is a size, which can take different values. It is thus in its size variable or variable. Variable ones are called also substitute symbols or unknown quantity. They seem to terms in formulas , and in equations .

The termVariable one becomes particularly in engineer and natural sciences, in particular in mathematics, the physics, which chemistry uses and in computer science.

The opposite of a variable is the constant, thus a fixed, constant value. The circle number Pi = 3,14… is for example no variable, but a constant. Physical dimension like the temperature or the pressure are against it typical variables.

Further examples of variable:

in an equation, for example a physical formula, one often regards, as a variable to change must ( the dependent variable), in order to fulfill the equation, if one changes another variable (those argument). If one gave the constant speed for example with a homogeneously moved body, then one can examine, how the put back distance (the dependent variable) behaves on change of the time (the argument). Turned around can be also examined,after which time (when dependent variable) a certain given distance (when argument) was put back.

Other example: One wants to know whether the color has an influence on the paragraph of a car. Then the color is the argument and thatParagraph the dependent variable. If one wants to know however whether the paragraph affects the color, then the paragraph is the argument and the color the dependent variable.