What Are the Nuances of Mathematical Symbols and Their Applications?

  • Context: High School 
  • Thread starter Thread starter jaysquestions
  • Start date Start date
  • Tags Tags
    Homework Random
Click For Summary

Discussion Overview

The discussion revolves around the nuances of mathematical symbols and their applications, including the differences between various types of brackets and their uses, the concept of corners in functions, and the interpretation of analytical methods in mathematics. Participants explore these topics through questions and clarifications rather than formal homework problems.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants inquire about the difference between brackets and parentheses, questioning the appropriate symbols for ordered pairs.
  • There is a discussion on whether the number of left brackets must equal the number of right brackets in mathematical expressions, with some asserting that they must always match.
  • Participants explore the meanings of "broadened" and "steepened" in relation to graph transformations, with examples provided to illustrate these concepts.
  • Questions arise regarding the definition of corners in functions and whether they are universally defined or depend on the specific function.
  • Clarifications are sought on what is meant by using an analytical method, with some suggesting it involves calculations rather than graphical analysis.
  • The representation of hyperbolas and other conic sections is discussed, with references to how they are formed by intersecting a cone with a plane.

Areas of Agreement / Disagreement

Participants express differing views on several points, particularly regarding the definitions and uses of mathematical symbols, the nature of corners in functions, and the interpretation of analytical methods. No consensus is reached on these topics.

Contextual Notes

Some participants note that the terminology and conventions used in mathematics may vary, leading to potential confusion. Additionally, there are references to specific examples and definitions that may not be universally accepted.

Who May Find This Useful

This discussion may be of interest to students and educators in mathematics, particularly those exploring foundational concepts and terminology in mathematical expressions and graphing.

jaysquestions
Messages
20
Reaction score
0
None of these questions are homework problems, they're just confusing things that homework has caused

1. In math, what is the difference between a bracket and a parenthesis? Also what about the right symbols for ordered pairs , is that strictly these [ ] or these { }

2. If you have lots of brackets (just to be clear, I mean these ( ) )... does the number of left hand brackets always equal the right hand brackets? For example,

## f(x) = (3(x^2 - 3) / x(x^3+6)) ## I realize it could be written a lot different, but I am just focused on the brackets.

..so when you are checking over a long problem, you can count the left brackets and make sure they = right brackets. Is that valid? (in English one right bracket can close multiple left brackets, which has never made sense to me. So math is different?)

3. What is he difference between "broadened" and "steepened" wrt graphs?

4. Are corners of a function defined and how do I know they are defined? (or does it all depend on the function?

5. What does the textbook mean when he says "use analytical method to determine..." Is he just saying make a graph and look at it?

6. Conic sections: Why are hyperbolas represented with two lines , taken from two cones, when circles and ellipses are represented using just one cone?

thank you for any answers
 
Mathematics news on Phys.org
jaysquestions said:
... does the number of left hand brackets always equal the right hand brackets?

Yes. If a closing parenthesis is missing, there is no reason to assume it belonged at the end. It's a mistake.

jaysquestions said:
n English one right bracket can close multiple left brackets, which has never made sense to me. So math is different?

I've never heard of this. Brackets and parentheses must always be used in pairs. The only exceptions are smilies and leetspeak.
 
LISP programming used to use the convention of a square bracket closing the program statement. It would basically close all remaining open parentheses.

Also there's a general convention in math to call "( )" parentheses and "[ ]" square brackets and "{ }" curly braces with some folks dropping the square and curly adjectives.

Using an analytical method means to use algebra rules, trigonometric, boolean, ... identities and Calculus rules to reduce an expression into a simpler form or to use numerical methods to get an answer. This is in opposition to graphing the function and determining things visually by inspection.
 
Last edited:
jaysquestions said:
None of these questions are homework problems, they're just confusing things that homework has caused

1. In math, what is the difference between a bracket and a parenthesis? Also what about the right symbols for ordered pairs , is that strictly these [ ] or these { }
In general there is no difference. There may be special cases. For example, you ask about "ordered pairs" being either [ ] or { }. I have never seen either of those. I have always seen (a, b) for ordered pairs.

2. If you have lots of brackets (just to be clear, I mean these ( ) )... does the number of left hand brackets always equal the right hand brackets? For example,

## f(x) = (3(x^2 - 3) / x(x^3+6)) ## I realize it could be written a lot different, but I am just focused on the brackets.
Yes, "brackets" ("braces", "parentheses") always separate a given section of a formula from the rest. You should never have a left bracket without a corresponding right and vice versa.

..so when you are checking over a long problem, you can count the left brackets and make sure they = right brackets. Is that valid? (in English one right bracket can close multiple left brackets, which has never made sense to me. So math is different?)
I have never heard of such an "English rule". Where did you learn that? Is it, for example, in Strunk's "The Elements of Style"?

3. What is he difference between "broadened" and "steepened" wrt graphs?
Pretty much just what it says. If you have a function, y= f(x), such that f(1)= 3, f(2)= 4, and f(4)= 7, so that the graph contains the points (1, 3), (2, 4), and (4, 7), then the graph of y=f(2x) satisfies f(2)= 3 and f(4)= 4 so contains the points (2, 3) and (4, 4). This new graph takes twice as long (2 to 4) to go from height 3 to height 4 a before (1 to 2) so has "broadened. On the other hand, the graph of the function y= 2f(x) contains the points (1, 6) and (2, 8). In going from x= 1 to x= 2 horizontally, it has gone, vertically, from 6 to 8 so is steeper.

4. Are corners of a function defined and how do I know they are defined? (or does it all depend on the function?
I have no idea what you mean here. A "function" is not a geometric object and so does NOT have "corners". Where did you see "corners of a function"? How were they defined where you saw the reference?

5. What does the textbook mean when he says "use analytical method to determine..." Is he just saying make a graph and look at it?
No, an "analytical method" (just "analytical method" without an article would be bad English!) is one that involves limits and calculations, not just looking at a graph. It might mean considering continuity and/or using limits to determine what asymptotes there are.

6. Conic sections: Why are hyperbolas represented with two lines , taken from two cones, when circles and ellipses are represented using just one cone?
Because that is the way they are created. circles, ellipses (and parabolas) have only one connected component because they are created by slicing a cone (grammatical point: strictly speaking a "cone" always has two parts, not just one. It is incorrect to say "two cones" or "just one cone". You are rather, referring to one or two components of a cone.) with a plane. In the case of a circle so that the plane is perpendicular to the axis of the cone, and only intersects one component, in the case of an ellipse so that it is between perpendicular to the axis and parallel to one side, so that it still slices through one component of the cone, in the case of a parabola parallel to the side of the cone so goes through one side of one component and is parallel to the other, and, finally, a hyperbola that crosses through both components.

thank you for any answers
 
jaysquestions said:
None of these questions are homework problems, they're just confusing things that homework has caused

3. What is he difference between "broadened" and "steepened" wrt graphs?
What do the words "broad" and "steep" mean to you?

4. Are corners of a function defined and how do I know they are defined? (or does it all depend on the function?
Corners of what function? You'll have to be more specific here.
5. What does the textbook mean when he says "use analytical method to determine..." Is he just saying make a graph and look at it?
If that were the case, then the textbook would say, "graph [whatever] to determine ..."

Analytical methods usually involve doing calculations of some sort.

6. Conic sections: Why are hyperbolas represented with two lines , taken from two cones, when circles and ellipses are represented using just one cone?
Look up how conic sections are defined by a plane which intersects the cone.

Some of these questions you could have answered yourself by doing a little research.

The web is a wonderful tool, but you've got to put forth a little effort to get it to yield its information.

Try using a search engine to answer some of these questions.
 
Hyperbolas come from double cones:

300px-Conic_sections_with_plane.svg.png

In this image, that would be #3. This is what https://www.physicsforums.com/members/hallsofivy.331/ meant when he said:

HallsofIvy said:
strictly speaking a "cone" always has two parts, not just one. It is incorrect to say "two cones" or "just one cone". You are rather, referring to one or two components of a cone.
 

Similar threads

  • · Replies 10 ·
Replies
10
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 3 ·
Replies
3
Views
4K
  • · Replies 23 ·
Replies
23
Views
2K
  • · Replies 19 ·
Replies
19
Views
6K
  • · Replies 8 ·
Replies
8
Views
3K
  • · Replies 4 ·
Replies
4
Views
1K
  • · Replies 3 ·
Replies
3
Views
2K