13.1 Graphs of Functions
1. Function is a relationship that expresses a variable (dependent) in terms of another variable (independent).
2. y is a function of x if and only if every value of x corresponds to only one value of y.
13.1.2 Graphs of Functions
1. A graph of function is a representation of the function as one or more lines on a coordinate plane.
2. When drawing graphs of functions, it is best to observe these few points:
· choose suitable scales for both axes.
· use at least three points to draw a straight line to ensure accuracy.
· use at least five points to draw a curve to ensure accuracy.