Questions tagged [precalculus]
Courses designed to prepare students for subsequent calculus courses
68
questions
2
votes
1
answer
361
views
Sources on inequity in precalculus sequence
I'm trying to put together some thoughts on the importance of a strong college precalculus sequence (mainly I'm thinking College Algebra, where much of my experience is) for addressing socioeconomic ...
18
votes
4
answers
3k
views
Why do we teach linear algebra in precalculus classes?
When I took precalculus, we learned about polynomials and how to factor them, we learned about trigonometry and lots of great and useful identities there, and we learned about matrices. They didn't ...
0
votes
2
answers
271
views
Differentiation in integer solutions
What would you suggest as examples to demonstrate as applications of differentiation in finding integer solutions of an equation for advanced level students?
Here you have one example which I have ...
29
votes
6
answers
3k
views
f(x+h) in the difference quotient
When teaching students how to compute the difference quotient in a precalculus or calculus class, we need them to evaluate the expression
$$\frac{f(x+h) - f(x)}{h}$$
for various simple functions, like ...
6
votes
3
answers
3k
views
Are there examples of central symmetry, without axial symmetry, in nature?
Examples of axial symmetry abound, but I could not find an example of pure central symmetry (that is, without axial symmetry)! Do you know of any? A butterfly shows axial symmetry, what shows point/...
1
vote
0
answers
116
views
Math curricula\programs or any experience using "The Road to Reality" as the\a primary textbook
Primarily a reference request, collaborator search-tips requests, and question-improvement request (including improveent by deletion and re-posting to more appropriate stack, meta, wiki, etc). Rank ...
7
votes
7
answers
1k
views
Write $y=\sqrt{3+x}$ as the composite of two functions
For the question "Write $y=\sqrt{3+x}$ as the composite of two functions", what if a student gives the answer $f(x)=\sqrt{3+x}$ and $g(x)=x$? This answer would be technically correct but it ...
2
votes
1
answer
121
views
Do properties of exponents apply only to positive real numbers? [closed]
A common rule given in textbooks is:
If $a$, $b$, and $x \in \mathbb{R}$, then $(x^a)^b=x^{ab}$.
Suppose I write:
$(-9)^{1/2}=(-9)^{2/4}=((-9)^2)^{1/4}=(81)^{1/4}=3$.
But this contradicts the fact ...
4
votes
2
answers
290
views
Do horizontal asymptote rules require function to be fully simplified?
I am teaching high school precalculus and have a textbook that gives the following preamble to its rules for finding horizontal and slant asymptotes of rational functions:
Suppose $f(x)=\frac{a(x)}{b(...
5
votes
3
answers
3k
views
What are some examples of great functions that are not too elementary (easy)?
I am teaching precalculus/basic calculus to my class (high schoolers of around 18 years of age), and I'm always searching for nice functions to plot and study (finding the domain, the function's sign, ...
6
votes
3
answers
450
views
How can you elicit the $\log x = {\log} \cdot x$ error?
You know the error, when you're watching a student work through an algebraic calculation to solve for a variable trapped in the argument of a function, usually $\log$ or a trig function, and you watch ...
0
votes
1
answer
266
views
Best PreCalculus Textbook
What is your favorite PreCalculus textbook for someone that needs to get their algebra skills up to snuff? Something comprehensive with some tricky problems. Stewart? Sullivan? Blitzer? Something ...
6
votes
2
answers
435
views
Is Trigonometry done differently in the US?
I'm Italian and I've watched some videos from Americans and noticed a weird thing. Let's talk about a linear trigonometric equation like this:
$$\sin x+\cos x+\sqrt3=0.$$
I've seen Americans solving ...
0
votes
0
answers
91
views
Is the AC Method of Factoring polynomials more popular and used by teachers than others methods of factoring polynomials?
This is an example of the AC Method:
$ x^2 + 16x +63 $
(1) $x² + 7x$ (2) $9x + 63$
(1) $x(x + 7)$ (2) $9(x + 7)$
so we have:
$x(x + 7)+ 9(x + 7)$
(1) with (2) The Result is:
$ (x+9)(x+7) $
I have more ...
0
votes
1
answer
195
views
Matriculation exams like in Europe
I just looked at matriculation exams from Finland. They have both basic and advanced level exams. Most US high school seniors could not pass the basic exam. If each US state were to create its own ...
1
vote
1
answer
420
views
Honors Precalculus: what topics to cut?
We’re precalculus honors teachers. In this year of Covid and reduced instructional time, what topics can we cut (Demana textbook) that would not hurt our kids in either calc AB or BC?
7
votes
3
answers
529
views
Why is isolating for $x$ taught before factoring?
I'm currently working on some precalculus packages for students who need review. For inspiration, I'm looking at some prealgebra books and I'm wondering why isolating for $x$ is taught before ...
1
vote
3
answers
559
views
When are students taught implicit and parametric representations of curves?
Do students learn implicit equations (such as $x^2+y^2-r^2 = 0$)
and parametric equations (e.g., $x=a t^2,\;y= 2 a t$)
in a first course in algebra,
which in the US would be early high school, maybe ...
2
votes
1
answer
89
views
Appropriate context for teaching derivative (undergraduate/graduate)
(Repost from MO, where the question will eventually be closed.)
This question is related to lectures I have to make concerning differential calculus in one variable, but the students are quite ...
4
votes
4
answers
582
views
How to word this exercise about converting "English" into interval notation?
I am writing an exercise for a precalculus homework assignment that deals with the topic of interval notation. The point of the exercise is to convert open, closed, and half open intervals described ...
12
votes
6
answers
3k
views
How do you explain concavity of a polynomial without any calculus?
How do you explain the concavity of a polynomial without any calculus?
As the title suggests, I am struggling to explain when given a graph of a polynomial, how we determine when it is concave up or ...
5
votes
2
answers
185
views
Is evaluating a Real Polynomial at a Complex Value a suitable task for Precalculus students?
In Korea, basically every teaching material for 10th grade math(about the level of precalculus) contains this kind of exercises in their first treatment of complex numbers:
Evaluate $f(x)=4x^4-8x^3+...
8
votes
3
answers
393
views
Algebra/trig/precalculus review questions that elicit common student errors
This semester I have decided to give students a simple question or two at the beginning of every calculus class that will trap them into making the most common errors that we all know...e.g. the ...
5
votes
2
answers
553
views
Which textbooks on College Algebra, Trigonometry, Pre-calculus, Calculus, Linear Algebra, ODE are written by world-class mathematicians?
For example, Trigonometry was written by Wolf-Prize winner Israel Gelfand, one of the top mathematicians in the 20th century. I am wondering if other world-class mathematicians have written textbooks ...
4
votes
3
answers
335
views
Is there a pre-calculus introduction to the formal definition of a limit?
To give an example of what I mean, I'll answer a similarly worded question: “is there a pre-calculus introduction to the derivative?” I would say yes, since there already are the ideas of a slopes of ...
44
votes
21
answers
7k
views
How to help new students accept function notation
I am struggling to help some of my new precalculus students accept function notation -- something new to them this term. I am looking for strategies to help them adopt this new notation.
Their main ...
4
votes
4
answers
1k
views
Best Way to Learn Trigonometry
What are the best resources to learn trigometry? I recently decided to pursue a BS in mathematics at uni. I used to fail all my math classes with D's or F's until I started teaching myself, and so far ...
4
votes
2
answers
415
views
Enlighten younger students about the concept of "procedural justice" in mathematics?
I am tutoring a 16-year-old student from my home country (in Asia) in, roughly speaking, precalculus. I would like to give him a feeling of procedural justice, so to speak, in modern mathematics, ...
9
votes
3
answers
215
views
Physical devices for exploring calculus or pre-calculus
I saw this partial derivative machine yesterday, and it got me excited about other physical devices for exploring calculus concepts in a "lab" setting (e.g. make a prediction, collect data, etc.) Do ...
8
votes
4
answers
710
views
A more rigorous approach to Precalculus
I am a pure mathematics PhD student and graduate teaching assistant at a major state university. During the summers here, teaching assistants are typically appointed to teach an entire course, rather ...
4
votes
2
answers
271
views
Why are we even studying cyclotomic polynomials?
My students found an exercise about cyclotomic polynomials in the AOPS precalculus text. They asked me why this construction exists in the first place and what it's good for... I am looking to give ...
10
votes
3
answers
410
views
The royal road to calculus
In the early 1900s Felix Klein lay out his vision for secondary mathematics curriculum. He wanted schools to teach calculus, so that universities would not be burdened by it. And at the core of the ...
12
votes
3
answers
688
views
Examples (for beginners) of real functions which are not given by elementary formulae
Question: What are good examples of functions $f: \Bbb R \rightarrow \Bbb R$ (or $f: D \rightarrow \Bbb R$ with $D \subseteq \Bbb R$) which are not just given by "a formula" (or finitely many formulae ...
2
votes
3
answers
3k
views
Good (natural) motivational examples for quadratic equations
I am looking for good motivational examples of how quadratic equations can naturally arise in real life for someone starting high school. The high school book my child is using just jumps into ...
1
vote
1
answer
426
views
How can I make "complex" graphs that combine multiple functions with a software?
Til today I've been using geogebra to sketch functions for my students quizzes or homework. Sometimes I use the ones that I found searching in google, but this takes a lot of time specially because I ...
1
vote
0
answers
69
views
How to introduce trigonometric ratios (HS) through a cognitive model?
I'm teaching a precalculus course and also taking a class on how to teach mathematics constructing a specific cognitive model for different topics. So, I have this assignment to build a cognitive ...
3
votes
2
answers
153
views
Should Measurement of Angles Using Degree (and perhaps Common Logarithm as well) be Avoided in Pre-Calculus?
People use degrees and radians to measure angles and though degree measurement is acceptable and is widely used in everyday life, it is not in the International System of Units and mathematically it ...
32
votes
8
answers
6k
views
Math topics that reward going beyond cookbook methods
Students fresh out of high school are often under the impression that mathematics is a discipline based entirely in recognizing the type of problem and applying an algorithm or cookbook method. These ...
3
votes
1
answer
359
views
Deriving Jerk Equations without using Calculus
I am thinking about the links between SUVAT equations (constant acceleration), and equations for motion when higher-order measurements are constant (for example, when jerk is constant, or snap is ...
6
votes
6
answers
1k
views
Ideas for a 2 weeks project focused in polynomial functions
Right now I’m teaching precalculus in high school and I want to propose a project to my students about polynomial functions. They already know enough about quadratic functions and we study variation ...
5
votes
3
answers
463
views
When discussing inverse functions, how can our notation and methods reinforce student understanding?
Yesterday in my precalculus class, I decided to teach students how to find the formula for an inverse function in a new way (to me).
In this curriculum, they have already used the notation $f^{-1}(x)$...
30
votes
10
answers
11k
views
Why do we teach even and odd functions?
I've been either a student or an instructor in Precalculus or Calculus 1 at about 6 institutions now, and teaching the definition of even functions (where $f(-x) = f(x)$) and odd functions (where $f(-...
6
votes
4
answers
1k
views
Functions, Domains, and Ranges in Precalculus
Possibly related, though of a different flavour.
Background
In most of the precalculus texts with which I am familiar, readers/students are given a crash course in set theory, handed the definition ...
6
votes
2
answers
387
views
How can I improve my problem solving/critical thinking skills and learn higher math?
I'm a rising sophomore in high school. So far, I've taken Algebra One, Two, and Geometry in school. I want to learn higher math such as precalculus/trigonometry, calculus, linear algebra, and more, so ...
12
votes
4
answers
1k
views
The Order in Pre-Calculus Textbooks
Every Pre-Calculus I have examined starts with functions in general, then polynomial and rational functions, followed by exponential and logarithmic functions and Trigonometry, and ending with ...
8
votes
1
answer
190
views
How can I deal with the time pressure of teaching a short course?
I am an undergraduate applied math student. In about a month, I will be teaching two nine-hour math courses (one precalculus, one calculus) to a small group of motivated high school students. My broad ...
14
votes
7
answers
961
views
How should I introduce the concept of a function to a precalculus student?
My brother has not taken a math class in $10-15$ years. He is studying for the GRE so I have been teaching him a chapter or two from my precalculus book. So far, he has learned (and excelled at) basic ...
8
votes
9
answers
14k
views
Requirements to learn calculus
I always was non math background student and programming is my hobby. I was attempting to program code instruction given here. Since I don't know calculus I'm stuck. I would like to know what are the ...
5
votes
1
answer
141
views
Consolidating three descriptions of a parabola in precalculus
I want to present these three descriptions of a parabolic curve to my precalculus class:
The graph of a quadratic function $f(x) = ax^2+bx+c$.
Given a line called the directrix and a point called the ...
6
votes
3
answers
938
views
Is there a more intuitive way to solve combined rates of work problems?
I am helping my brother study for the GRE and we have come across some problems like this in my old precalculus textbook:
1) Karen and Betty have been hired to pain a house. Working together, they ...