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This article explores the use of Computer Algebra Systems (CAS) and MATLAB in 1st year collegiate math courses. It discusses the differences between CAS and MATLAB, their applications in calculus, and the integration of these tools into the curriculum. The author also addresses the challenges of using either choice and provides insights into their distinct natures.
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CAS or MATLABin 1st year collegiate math? Matthias Kawski Arizona State University Tempe, U.S.A. http://math.asu.edu/~kawski This work was partially supported by NSF grants DMS 00-72369 and DMS 01-07666. http://math.asu.edu/~kawskikawski@asu.edu
Professional user of both CAS an MATLAB:e.g. MAPLE: curvature of optimal control,MATLAB: simulate ½ conductor industry supply chains http://math.asu.edu/~kawskikawski@asu.edu
Outline • Brief intro-contrast: CAS versus MATLAB • Brief survey: Matt K and his environment why this question? • (Traditional) calculus is just algebra ! • MAPLE and calculus ??? • MATLAB and calculus ??? • The next courses: MAPLE versus MATLAB http://math.asu.edu/~kawskikawski@asu.edu
Computer ALGEBRA Systems • MATHEMATICA, MAPLE, DERIVE, …. • $ 1000 professional, $ 150 student version • can do state-of-the-art numerics, graphics, ….but main data structure is symbolic expressions(NOT numbers). • Can do virtually all symbolic calculations thatcan be done by hand, but faster, much more reliably (fewer mistakes), and more systematically • can call MATLAB from inside CAS (inconvenient) http://math.asu.edu/~kawskikawski@asu.edu
CAS example http://math.asu.edu/~kawskikawski@asu.edu
MATLAB • $ 1000 professional, $ 150 student version • state-of-the-art numerics, graphics, ….main data structure is matrices of floating point numbers • professional use in sciences, engineering, math,… • fast ! • can “call CAS” from inside (“symbolic toolbox”) http://math.asu.edu/~kawskikawski@asu.edu
MATLAB example Most simple academicapplication:image processing…..(e.g. basic .gif imageoff the WWW, say a 60 x 80 pixel image) http://math.asu.edu/~kawskikawski@asu.edu
Institutional background • Arizona State University:public university in rapidly growing metro area50 000 student total12 000 in math each fall semester 7 000 below calculus 300 “events” of average size 40 • majority of calculus I-III, diff equns, linear algebraare engineering majors • engineering college very progressive http://math.asu.edu/~kawskikawski@asu.edu
Integrated curricula in 1990s technology intensive, team-oriented, project-driven,…..(Intro2Engineering, CAD, English, Physics, Calculus,…..) http://math.asu.edu/~kawskikawski@asu.edu
Professional technology integrated • All students have at (almost) all times access to professional computer software • especially during the exams! i.e. exams needed to change (usually including internet access) • typically, one or two computers at each table,but do not teach in traditional computer lab set up in rows where studenst hide behind screens…. http://math.asu.edu/~kawskikawski@asu.edu
Professional technology for math Courses under consideration:prep for calculus, calculus, mutli-var and vector calculus, diff equations, (linear algebra) • …, papyrus • abacus • slide-rule • logrithm table • hand-held calculator • graphing calculator • Computer Algebra System: MAPLE, MATHEMATICA • professional numerical package: MATLAB http://math.asu.edu/~kawskikawski@asu.edu
Calculus is an algebra course ? • (algebra of ) limits, especially rational functions(L’Hopital’s rule …. everything via Taylor expansion) • derivatives versus derivations • antiderivatives (as opposed to integrals) • “proof”: CAS can get 90% right on almost any final exam • The only thing that that matters is what is on the final exam: Traditional calculus is a course in algebra! http://math.asu.edu/~kawskikawski@asu.edu
Derivations versus derivatives • Derivatives are analytic objects, defined bylimits, approximability by linear objects… • Derivations are algebraic objects that are defined as linear maps that “satisfy the Leibniz (product) rule”: D(fg)=(Df)g+f(Dg) http://math.asu.edu/~kawskikawski@asu.edu
Derivations versus derivatives • Derivatives are analytic objects, defined bylimits, approximability by linear objects… • Derivations are algebraic objects that are defined as linear maps that “satisfy the Leibniz (product) rule”: D(fg)=(Df)g+f(Dg) • The only thing that that matters is what is on the final exam: Traditional calculus is a course in algebra! http://math.asu.edu/~kawskikawski@asu.edu
Our engineers • every year they come back asking more loudly why we don’t use MATLAB also in 1st year calc. • so far held them at bay, compromise: calculus w/ CAS, introduce MATLAB in some DE sections, LA mostly w/ MATLAB…. • main motivation for this presentation and article:The clients seem to be very ill-informed about • the very distinct natures of either alternative • of how they mesh w/ the requested curriculum • and how problematic it is to INTEGRATE either choice http://math.asu.edu/~kawskikawski@asu.edu
Easy way out • MATLAB is useless on traditional calculus exams,i.e.no problems with exams when using MATLABMATLAB becomes an “add-on”for explorations, plotting, some checking,but is certainly not “integrated” http://math.asu.edu/~kawskikawski@asu.edu
CAS gives trouble • CAS by itself earns A on traditional calculus exam.i.e. either • need to completely redesign exams,or • prohibit CAS on exams. • Choice I is very hard, but it can be done (10 +years …) • Choice II is again just an “add-on”, no integration. • but neither one makes my engineers happy at this time http://math.asu.edu/~kawskikawski@asu.edu
A closer look at the divergence • Calculus as “mathematics of continuous change”… changing objects = functions • Calculus as the study of • differentiable functions, and • integrable functions • Take closer look at functions in CAS / MATLAB http://math.asu.edu/~kawskikawski@asu.edu
> y : = x ^ 2 ; > f : = s -> s ^ 2; > subs ( x = 3 , y ); (“plug in”, “substitute”) > f ( 3 ); (“evaluate at”) > plot ( y , x = - 5 . . 5 ); > plot ( f , - 5 ..5 ); > diff ( y, x ); (sciences: diff. w.r.t. variable) > D(f) ; (no x needed for derivative) Expressions versus functions in CAS http://math.asu.edu/~kawskikawski@asu.edu
Functions in CAS • Traditional language: • “find a function that …” • “find the aniderivative of …” http://math.asu.edu/~kawskikawski@asu.edu
Derivations in CAS http://math.asu.edu/~kawskikawski@asu.edu
Derivations in CAS http://math.asu.edu/~kawskikawski@asu.edu
MATLAB: basic functions http://math.asu.edu/~kawskikawski@asu.edu
MATLAB: advanced functions 1 externally defined: usual trouble pathnames, write-protected networked environmentsfunction handles… http://math.asu.edu/~kawskikawski@asu.edu
MATLAB: function topics • Nearly ideal for numerical differentiation and numerical integration, including investigationsof the limiting processes… indeed, an almost perfect match for very reformed calculus course • incl. even functions defined as antiderivatives… • hard: function composition, inverse functions, …. http://math.asu.edu/~kawskikawski@asu.edu
Summary and conclusions • MATLAB is a very easy add-on, useless in exams • CAS, but not on exams, is just another add-on • CAS, incl. on exams, requires dramatic rethinking • For traditional course CAS is much easier match • Major challenge: use MATLAB (w/ “integration” demand) as “vehicle” to implement (next step of) true calc reform? http://math.asu.edu/~kawskikawski@asu.edu
Compare linear algebra • We now have two parallel linear algebra courses: • target: Jordan canonical form = MAPLE course • target: Singular Value Decomposition = MATLAB • Similar with differential equations • Maybe next, two calculus courses… • one course that is essentially algebra of mappings • one course that studies continuous change of numerically defined functions http://math.asu.edu/~kawskikawski@asu.edu
A * c = y, c = ???clearly an undetermined linear system ofn = 4 equations in m = 1 unknown(s).What should division by coefficient matrix mean? http://math.asu.edu/~kawskikawski@asu.edu
Summary • Don’t take your engineer’s wishes lightly: Either way it will be a lot of work, and true integration will necessarily may radically change the course – how much is wanted? • Both CAS and MATLAB offer to greatly expand students’ horizons beyond the traditional algebra-oriented 1st year collegiate math courses • CAlgebraS are considerably easier to integrate into more traditional courses • MATLAB most typically is only an “add-on”, – unless the courses are dramatically reformed. http://math.asu.edu/~kawskikawski@asu.edu