Questions regarding the plotting or graphing of functions. Questions about graphs with vertices and edges should use the (graph-theory) tag instead. (STUB)

learn more… | top users | synonyms (2)

322
votes
10answers
346k views

Is this Batman equation for real?

HardOCP has an image with an equation which apparently draws the Batman logo. Is this for real?
2
votes
1answer
135 views

Can the graph of $x^x$ have a real-valued plot below zero?

The function $f(x) = x^x$ gives a complex number only if x has an even denominator. I'm not sure about irrational numbers. Why, then, is the best graph I can find of that function that of Wolfram ...
2
votes
3answers
615 views

Define a graph with segments or boundaries

This question is quite simple relative to the normal content on this site. (and please rename the title as I don't know what the proper definition is) Is it possible to have a function such as: $y = ...
11
votes
5answers
1k views

Why aren't the graphs of $\sin(\arcsin x)$ and $\arcsin(\sin x)$ the same?

(source for above graph) (source for above graph) Both functions simplify to x, but why aren't the graphs the same?
6
votes
5answers
1k views

Is there any equation for triangle?

Like there's an equation of a circle, is there any equation of a triangle? I've been trying to build one and the closest thing I've managed to do is to create an equation of 2 lines and use the $x$ ...
4
votes
2answers
286 views

Plotting graphs using numerical/mathematica method

From the author's equation 13, 14 We can write by inserting V''(A)=0, Solving for R we get, $$R= \frac{6^{D/4} \sqrt{D}}{\sqrt{-2^{1+\frac{D}{2}} 3^{D/2}+3 2^{1+D} A-3^{1+\frac{D}{2}} A^2}}$$ Now ...
2
votes
1answer
349 views

Calculating closest and furthest possible diagonal intersections.

Calculating closest and furthest possible diagonal intersections. Please refer to the image attached. It represents a $2D$ grid with the following properties: The grid origin is $(1,1)$ at the ...
4
votes
6answers
3k views

Plot $|z - i| + |z + i| = 16$ on the complex plane

Plot $|z - i| + |z + i| = 16$ on the complex plane Conceptually I can see what is going on. I am going to be drawing the set of points who's combine distance between $i$ and $-i = 16$, which will ...
3
votes
1answer
808 views

One algorithm for drawing graph of implicit function

All! Does anybody know who is author of algorithm described here and is the proposed solution correct?
2
votes
1answer
5k views

Boxplots and bar graphs

I'm studying for the GRE and came across several questions that I was unable to answer in a practice booklet, even after looking at the answer and trying to work backwards, and searching google and ...
1
vote
5answers
232 views

“Plotting” an equation

I have an equation like $$ (x - a)^2 + (y - b)^2 = r^2 $$ that represents a circle. I need to "plot" it very basically with a programming language. Computer graphics coordinate generally use the ...
3
votes
1answer
499 views

Using equations to draw out complex objects

How do people come up with equations of curves to draw out complex objects? Some popular examples would include: batman curve & PSY curve. This stackexchange link explains the rationale for the ...
2
votes
2answers
63 views

Help me conclude a statement about two points given the following…

Two points on the graph of $y=kx^p$ are labeled $A$ and $C$. Point $A$ has coordinates $(a,b)$, where $0<a<1$ and point $C$ has coordinates $(c,d)$, where $1<c$. If we are told that that the ...
2
votes
4answers
112 views

Function generation by input $y$ and $x$ values

I wonder if there are such tools, that can output function formulas that match input conditions. Lets say I will make input like that: $y=0, x=0$ $y=1, x=1$ $y=2, x=4$ and tool should ...
2
votes
4answers
168 views

Solving a quadratic Inequality

My question is: Solve $$9x-14-x^2>0$$ My answer is: $2 < x < 7$ Though I know my answer is right, I want to know in what ways I can solve it and how it can be graphically represented. ...
1
vote
2answers
59 views

Graph of the function $[\frac{1}{x}]$

I'm interested in the graph of the function $[\frac{1}{x}]$. may seems simple, also I graphed it myself. But there is difference between my solution and the manual solution. Here is the solution of ...
0
votes
1answer
33 views

Estimate growing graphs

Lets make my scenario not generic just so that i could use particular terms Say i have a graph of population per year of someplace over some decades Lets say the graph is like this How can i ...
-4
votes
2answers
108 views

Several questions about trigonometry and functions [on hold]

Any help on any of these questions is appreciated. I am studying for my finals and I couldn’t do these questions. Please help. Prove that $\sin^2(x)-6\sin(x)-5=0$ has more than one solution for ...
25
votes
2answers
5k views

Cannabis Equation

How can an equation for the following curve be derived? $$r=(1+0.9 \cos(8 \theta)) (1+0.1 \cos(24 \theta)) (0.9+0.1 \cos(200 \theta)) (1+\sin(\theta))$$ (From WolframAlpha)
13
votes
3answers
3k views

Best software to take math notes?

I have read some old discussions about this topic and would like to get some up-to-date advice, if possible. How can I take math notes, write formulas and draw graphs on my pc (win 7), the easiest ...
14
votes
12answers
2k views

How to explain the perpendicularity of two lines to a High School student?

Today I was teaching my friend from High School about linear functions. One of the exercises we had to do was finding equations of perpendicular and parallel lines. Explaining parallel equations was ...
6
votes
1answer
187 views

Very interesting graph!

I found a VERY interesting graph on http://www.xamuel.com/graphs-of-implicit-equations/. It looked very, very cool, but the equation of the graph is so simple! Here is the image of the graph: My ...
3
votes
4answers
3k views

What is a good graphing software?

What is a good graphing software ? The one that has the ability to accept an equation (linear, quadratic, etc.) from users and output a graph for that equation (software equivalnet of T1-84 graphing ...
9
votes
2answers
503 views

Draw graph of $\frac{1}{f(x)}$ from graph of $f(x)$

If I know the graph of $f(x)$, how do I draw the graph of $\frac{1}{f(x)}$?
1
vote
1answer
409 views

Parametric Equations of an Oblique Circular Cone

I am trying to determine the parametric equations for a specific shape of an oblique circular cone with no success. Exhaustive web searchs and many texts have not been fruitful as regards ...
3
votes
1answer
750 views

Can you write a non-piecewise equation that describes an arbitrary shape?

This batman equation thing got me thinking: for an arbitrary curve drawn on the Cartesian plane, can you write a corresponding equation which is not piecewise? What about closed shapes, a la the ...
2
votes
2answers
63 views

Strange graph problem

I'm trying to figure out this question: in the Cartesian coordinate system, how many grid points (x,y) satisfy $(|x|-1)^2 + (|y|-1)^2 < 2$? When I plugged it in to a graphing calculator, it didn't ...
2
votes
2answers
7k views

How do I reflect a function about a specific line?

Starting with the graph of $f(x) = 3^x$, write the equation of the graph that results from reflecting $f(x)$ about the line $x=3$. I thought that it would be $f(x) = 3^{-x-3}$ (aka shift it three ...
1
vote
2answers
91 views

Formula for solving for Cx and Cy…

I'm trying to create a formula to find the third point in a triangle based on two known points and three known sides. Known Sides: $AB, BC, AC$ Known Points: $A(x, y), B(x, y)$ Unknown Points: ...
1
vote
3answers
309 views

Can we have an equation for any graph?

I was wondering, can we have an equation for any graph even the most zigzagged one?
1
vote
1answer
341 views

Plotting a Function of a Complex Variable

I've been teaching myself complex analysis using "Introductory Complex Analysis" by Richard A. Silverman, and I'm a few chapters in and still have no clue how to plot anything. I know that $$ z = x + ...
1
vote
2answers
3k views

How do I determine the increasing order of growth of a set of functions?

I've been struggling with a homework-like problem (I'm a self-studier) and having trouble understanding the 'hints' I've already received. Please forgive my lack of knowledge around terminology. ...
0
votes
0answers
12 views

Mathematical/graphical implications of representing double integral of changing acceleration (which gives displacement) on a 3d plane.

Lets assume a function a = |sin t| for acceleration over time. If we integrate it, we get instantaneous velocity. I have been told that integrating a function provides me with the area under the ...
0
votes
2answers
1k views

About balanced and complete binary tree

I found this and I just couldn't verify it. How come it is true? The maximum number of nodes that a balanced binary tree with depth $d$ is a complete binary tree with $2^d-1$ nodes. Let say I have ...
-3
votes
1answer
137 views

Giving the domain and range of an equation. *not same problem as previously asked question* [closed]

I need help with a problem. *not same as a question i previously asked, it has a different question!* noting because someone downvoted... Given the function f(x) has a domain D: {-3,-1,0,2} and a ...
5
votes
5answers
115 views

Points on $(x^2 + y^2)^2 = 2x^2 - 2y^2$ with slope of $1$

Let the curve in the plane defined by the equation: $(x^2 + y^2)^2 = 2x^2 - 2y^2$ How can i graph the curve in the plane and determine the points of the curve where $\frac{dy}{dx} = 1$. My work: ...
4
votes
4answers
5k views

How to find the angle between two straight line equations?

The Problem There are two straight lines with equations as follow y=-2x+10 and y=-3x+6 their point of intersection is (2,6) and i am asked to find the angle between them ? A detailed and easy ...
2
votes
4answers
96 views

Understanding the graph for $x^y = y^x$

I graphed $x^y=y^x$ and it is a union of the line y=x, with some other curve. So my first question is, how do I derive that other curve? My next question is, why don't I get the same graph when I ...
2
votes
2answers
4k views

Piecewise function plot in Matlab

Is it possible in Matlab to plot an even piecewise function like: $ f(x) = \begin{cases} 3t , 0 < t < \pi \\ -3t , -\pi \le t \le 0 \end{cases}$ which has a period of $2\pi$. I ...
2
votes
1answer
176 views

What is the purpose of defining the notion of inflection point?

What is the purpose of defining inflection point? I know that it is defined to be the point where the second derivative is zero and the second derivative sign changes. It has to have some purpose ...
2
votes
3answers
324 views

Do all polynomials of even degree start by decreasing as you plot from $-\infty$ upward?

Polynomials of degree 2, if the first term is positive, starts descreasing. Polynomials of degree 3, if the first term is positive, starts increasing. is this constant? like.. Polynomials of ...
1
vote
1answer
25 views

How do you graph a fractal on a line, as a function of time and position?

I'm writing ANSI C code for work and just got working my LED Light Show Library. The first project it's going on is a sound bar with 10 volume indicator (1-color (white)) leds that are lined-up. ...
1
vote
1answer
52 views

How To Slice $Re(1/(1+z))$ Into A Cartesian Function For Any Angle?

The complex function $\frac{1}{1+z^2}$ may be broken into real and imaginary components: $$Re(\frac{1}{(1+z^2)})=\frac{1+x^2-y^2}{(1+x^2-y^2)^2+4x^2y^2}$$ ...
1
vote
2answers
3k views

Given the graphs of f(x) and g(x) sketch the graph of (f-g)(x) on the same grid.

I have been working on this problem for almost half an hour and can't figure out how to sketch the graph any help would be appreciated.
1
vote
2answers
299 views

Graph of an infinitely extending rollercoaster loop

I am trying to find the equation for the form that is in the picture. Basically it is an infinitely extending roller coaster loop. I just can not find the magic words in Google. Any suggestions? ...
0
votes
1answer
30 views

Integrating function of acceleration to obtain displacement

Lets assume a function a = |sin t| for acceleration over time. If we integrate it, we get instantaneous velocity. Now i have taken a limit for time. How will this graph look like? I have been told ...
0
votes
0answers
32 views

Graphing complex plane curves

This may be just as much a question about computers as a question about math. Suppose we have a complex curve $C\subset\mathbb{CP}^2,$ given by some $f(r,s)=0.$ Picking an affine chart, we can view ...
0
votes
1answer
899 views

How do I get MATLAB to use custom labels for data in plots? [closed]

By this I mean, I have data that I would like to plot but each data corresponds to a different drug (aripiprazole, olanzapine, quetiapine and risperidone) and I would like the name of the drug to be ...
0
votes
2answers
121 views

What exactly is the complex plane, and how is it useful?

A lot of functions are defined on the complex plane, like the Gamma function: the Lambert W function, etc. But I have no idea about what the complex plane means and how it's useful, or just ...
0
votes
1answer
197 views

Calculate closest point without calculating hypotenuse or linear length in 2D space.

Given n number of (x, y) points, I want to find out which is closest (linear distance) to the point of origin (1, 1). Both x and y will always be positive integers. ...