Linear functions are every one function, which have this prescription: f:y = ax + b, where a anb b are real numbers. Very particular case is, if a = 0, because then the function will have this prescription: f:y = b and this is the constant function (some people say the constant function did not the linear function). Linear functions have very nice graphs, because it is in every case straight line. If b = 0, the straight line intersects the axises in point [0, 0].
the graph of function y = x
The next property of linear function is depand on argument a. If a > 0, the linear function is increasing function and if a < 0, the function is decreasing function. The graph of function f:y = ax will be axially symmetrical with axis y with function g:y = −ax.
The graph of decreasing linear function y = −2x
Protract graph of linear function f:y = −3x +1.
We can protract this graph very easy. We know, every graph of linear function is a line. Than we have to know coordinates of two points. f(0) = 1 and f(1) = −1. The first coordinate is [0, 1] and the second [1, −2]. Now we have enough informations about the graph and we can protract it:
The linear function f:y = −3x +1
