This site is a sub collection of a larger set by Philippe Laval containing a variety of explorations. It is a self-contained collection of Java Applets that can be used in the teaching and learning of mathematics.
The Quadratic Functions applet investigates the relationship between the coefficients of the quadratic function (in both standard and general form) and the graph.
Target Student Population:
Students in a beginning, intermediate or college algebra course.
Prerequisite Knowledge or Skills:
The applets are self-explanatory and could easily be used by any mathematics student without assistance, however may be most effective if preceded by an instructor demonstration and explanation of terms.
Type of Material:
Computation, graphics and simulation.
classroom demonstrations; student explorations
It requires a "Java-enabled" browser.
Evaluation and Observation
The Quadratic Functions page contains two applets: ?Standard Form: Role of ?a?, ?b?, and ?c?? and ?Vertex Form: Role of ?a?, ?h?, and ?k??. Its features are best used initially as a demonstration by the instructor, followed by student experimentation.
The applets allow the user to enter values for ?a?, ?b?, and ?c? for the ?Standard Form? applet and and ?a?, ?h?, and ?k? for the ?Vertex Form? applet using a scroll bar. Accuracy to the tenth place is provided. As the scroll bar is moved, the corresponding graph is simultaneously updated.
As the scroll bar is moved the screen flickering can be an annoyance.
Potential Effectiveness as a Teaching Tool
Both applets effectively allow the user to explore how changing the parameters affects the parabola. The applets can be used to visually understand the constants in the two forms of the quadratic.
The applet does not provide background information on the mathematical concepts or ask the students questions that would lead to specific conclusions. As a result, the user must be given background information on the concepts to effectively understand the purpose of the demonstration.
Ease of Use for Both Students and Faculty
Students will need no explanation to use these applets, although there is an itemized explanation available just below the applet.
The scroll bar allows easy entry of values for the constants. Right and left arrows on the scroll bar assist the user in selecting specific values and consecutive values accurate to the tenths place. The simultaneous appearance of the corresponding graph allows the user to visualize the change in the graph that occurs as the parameters are increased or decreased.
The values shown for each of the constants are in textboxes that are not editable. Either presenting these as labels or allowing the student to enter values and having the graph adjust according to the entered values would make the applet easier to use.