ERIC Number: EJ1153378
Record Type: Journal
Publication Date: 2017
Pages: 10
Abstractor: ERIC
ISBN: N/A
ISSN: ISSN-0819-4564
EISSN: N/A
Available Date: N/A
Transforming Functions by Rescaling Axes
Ferguson, Robert
Australian Senior Mathematics Journal, v31 n1 p19-28 2017
Students are often asked to plot a generalised parent function from their knowledge of a parent function. One approach is to sketch the parent function, choose a few points on the parent function curve, transform and plot these points, and use the transformed points as a guide to sketching the generalised parent function. Another approach is to modify the parent function sketch to reflect, in turn, the impact of each of the generalised parent function's parameters. Students sometimes have difficulty with these approaches, because the precise shape of the generalised parent function may not be obvious to them from the few transformed points or they may not be clear about the impact of the generalised parent function's parameters. This paper presents an alternative approach to seeing what the generalised parent function looks like that is simple, foolproof, and does not even require plotting the generalised parent function. The alternative approach takes advantage of the fact that a rescaling of the parent function's axes changes it into the generalised parent function. Two benefits of the alternative approach are that it makes obvious to students that generalised parent functions are equivalent to parent functions and illustrates the impact of each of the generalised parent function's parameters.
Descriptors: Mathematics, Mathematics Instruction, Equations (Mathematics), Secondary School Mathematics
Australian Association of Mathematics Teachers (AAMT). GPO Box 1729, Adelaide 5001, South Australia. Tel: +61-8-8363-0288; Fax: +61-8-8362-9288; e-mail: office@aamt.edu.au; Web site: http://www.aamt.edu.au
Publication Type: Journal Articles; Reports - Descriptive
Education Level: Secondary Education
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A
Grant or Contract Numbers: N/A
Author Affiliations: N/A