reaaliarvofunktio

A reaaliarvofunktio is a mathematical function where both the domain and the codomain are sets of real numbers. This means that for every input value from the domain, the function assigns a unique output value that is also a real number. In simpler terms, a real-valued function takes real numbers as inputs and produces real numbers as outputs.

The domain of a real-valued function is the set of all possible input values for which the function is defined. The codomain is the set of all possible output values, though not all values in the codomain may be attained by the function. The set of all attained output values is called the range of the function.

Real-valued functions are fundamental in calculus and many areas of mathematics and science. They are used to model relationships between physical quantities, such as the relationship between time and distance, temperature and pressure, or the price of a good and its demand. Common examples include linear functions like f(x) = 2x + 1, quadratic functions like g(x) = x^2 - 3, and trigonometric functions like h(x) = sin(x). The graph of a real-valued function of one variable can be visualized in a two-dimensional Cartesian coordinate system, with the domain typically represented on the x-axis and the range on the y-axis.