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

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General Cartesian/Rectangular Equation for Polar Rose ($r=\sin(k\theta)$)

How do I convert the Polar Equation $r=\sin(k \theta)$ to Cartesian Equation? I understand that $r^2=x^2+y^2$ and that $x=r\cos\theta$ and $y=r\sin\theta$, but no matter how I try to arrange them it ...
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1answer
29 views

Graphing function with polar coordinate

I am studying polar coordinates and I am not understanding what's the practical method for graphing this relation: $$r = \frac{1}{2} + \sin \theta, \text{for } 0 < \theta < 2\pi$$. I plotted ...
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1answer
351 views

What is a moving average system?

Can someone elaborate on what a moving average system is? I know that the system is defined as: $$y[n] = \frac{x[n] + x[n-1] + x[n-2]}{3}$$ How would we draw $y[n]$ given that we have a graph with ...
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1answer
606 views

Plotting power-law fit in cumulative distribution function plots

In "Power-law Distributions in Empirical Data", the authors give several examples of alleged power-laws. For instance, they plot node degree distribution of the Internet like this (p. 24): where ...
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3answers
36 views

Can we determine uniform continuity from graphs?

Can we know from the graph of a function that whether the function is uniformly continuous or not? If the set on which the function is defined is not compact, so what one can say in that case?
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2answers
39 views

From the graph find the number of solutions.

The figure below shows the function $f(x)$ . How many solutions does the equation $f(f(x))=15$ have ? $a.)\ 5 \\ b.)\ 6 \\ c.)\ 7 \\ d.)\ 8 \\ \color{green}{e.) \ \text{cannot be determined from ...
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2answers
36 views

plot graph of function $f(z)=\frac{1+z}{1-z}$

I am not able to plot graph of function $f(z)=\frac{1+z}{1-z}$. can anyone tell me how to do this without using any software?
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1answer
306 views

Plotting discrete time signals involving sumations in matlab.

Many of the examples I've encountered while looking for an answer are simple functions that do not involve summations. Suppose I have the following function; ...
21
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4answers
766 views

Plot of a … Square?

Well there are equations which can plot a square like : $|x-y|+|x+y|=a$ But how about this equation: ? (At the end ... bear with me!) [Here I have taken $a = 1$] Plot of $$x^2 + y^2 = a^2$$ ...
3
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1answer
37 views

Conversion between trig functions and hyperbolic trig functions

Using trig identities we can see that $\sin^2 x + \cos^2 x = \tanh^2 x + \text{sech}^2 x = 1$ , and so the parametric graph $(\cos t, \sin t)$ is similar to $(\text{sech} t, \tanh t)$. The first ...
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0answers
48 views

Determine null, extreme and inflection points of function $f(x)=\frac{x+e^x}{x-e^x}$

This function has a null point, but I can't compute it from equation $f(x)=0$ which gives $$\frac{x+e^x}{x-e^x}=0$$ $$x+e^x=0$$ How to compute this equation? Extreme points can be computed from ...
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0answers
12 views

plot.ly question: how to to a scatter plot with one color for each dot [closed]

I need to create a plot in which each dot corresponds to one color, using the online version of plot.ly. I saw that its possible to do this by adding a column with the codes of the colors in the data ...
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0answers
39 views

Market Equilibrium & Calculus

I am a math nerd, but I'm working on my majorly lacking derivative analysis calculus. Trying to break into better understanding market equilibrium. I found some example questions that I am working ...
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1answer
20 views

Trouble understanding this graph sketching question

I have come across a question online that I decided to have a stab at; it goes like this: Question Let $f(x) := ax - \dfrac{x^3}{1 + x^2}$ where $a$ is a constant. (i) Show that if $a \geq ...
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0answers
11 views

List of graph data points, need accurate calculation/estimate formula for excel

So I'm working on a small project that will use a calculation in excel, I'm nearly there and the only piece missing is being able to accurately estimate a data point from the following set of data ...
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6answers
501 views

Why is the second derivative of an inflection point zero?

I wanted to know why is that so. I am just lost and want a detailed explanation.
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1answer
31 views

Website for plotting many linear equations

I am trying to find a site where I can paste a bunch of lines of form $y=mx+b$ and see them in a single graph. Wolfram Alpha has very limited space to do this, and other sites require that you enter ...
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1answer
34 views

smoothing linear graph but keep the spikes

how can I smooth a linear graph, but keep the spikes ? the graph are speed points per second, so it goes up and down frequently (like sinus curve), but sometimes there are spikes, like the speed ...
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1answer
13 views

Implement a y-ceiling on a slope function without domains

I'm working on a computer software application, dealing with very large quantities of numeric data, and I'd prefer to remove the domain conditions from this graph to help boost performance. Right now ...
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1answer
20 views

Problem withe differential equations and plot function [closed]

I Have a little problem . I wrote this function ( function describe dynamics of ball-hoop system): ...
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2answers
36 views

Is there a horizontal asymptote in $y =\frac{ x}{x^2 + 1}$

$$y = \frac{x}{x^2 + 1}$$ I was trying to sketch the graph of the above function but have no idea how to draw the rest after drawing the two concaves. I saw the graph of this function from a ...
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0answers
21 views

Matlab, Extracting Particular Values from an Excel File

If I have a table of values in Matlab ( here I have a 40k rows, and about a dozen columns), how can I read only particular values from each row? My goal is to extract some of the values from each row, ...
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0answers
81 views

What are some of the iconic mathematical images ever done in 2D, 3D and 4D? I've mentioned just a few

Since I'm on my school break I'm trying to visualize mathematics, I encountered a visualization of the following(3D). Deformation of the Riemann surface of an Algebraic function by Anatoly ...
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1answer
2k views

Linear Programming: Three variable graphical solution

A small bank offers three type of loans: housing loans at $8.50$% interest, education loans at $13.75$% interest rates, and loans to senior citizens at $12.25$% interest. Further, it needs to ...
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2answers
25 views

Points of intersection of two functions

Through the following steps I found the x-coordinates of the intersection points of two functions: $(x)= -x^{2}+3x+1\: and\: g(x)=3/x $ The numbers I found are x=(1, 2, 3) But on the graph, one of ...
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2answers
19 views

Determining the conditions such that the graph f resembles the given graph

I am pretty stuck on these problems, as I am not even sure where to really start with them. In Exercises 65–70, determine conditions for the coefficients of $$f(x)=ax^3+bx^2+cx+d$$ such that the ...
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0answers
37 views

Sketch the level curves of the function $f(x,y) = (x+y)^4$

My attempt: Let $$z = (x+y)^4 \iff \pm \sqrt[4]{z} = (x+y)$$ Since $z$ is a constant, $\sqrt[4]{z}$ will also be a constant. $$(x+y) = \sqrt[4]{z} = c \iff y = -x + c$$ So the contour plot will ...
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3answers
128 views

Get equation for a curve which intersects x at seemingly randomly distributed points?

Is there any type of function that when graphed would show a curve which intersects the x axis multiple times, with each point being an arbitrary distance from the last? I mean, not like a trig ...
4
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3answers
169 views

How can I plot this function that has a fraction that has an absolute value in the denominator?

I have this piecewise function: $$f(x)=\begin{cases} \dfrac{x^2-x-2}{|x-2|}, & x \neq 2 \\ 0, & x = 2\text{.} \end{cases}$$ I can't figure out how to graph it. I punched these numbers into ...
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3answers
39 views

Plotting a part of curves (with possible solution as an attempt)

I may mess up with this question! I plotted them using http://www.desmos.com/calculator How to plot only a part of some curves? For example: Plot of $y=x^2$: But if i want to plot the ...
2
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2answers
91 views

Changing the angle of the vertical and horizontal axis of Sine curve

Suppose we have $f(x)=\sin{(x)}$ The plot of $f(x)$ : Suppose I want to modify the graph by : Changing the angle of horizontal axis: (Plane rotation...so both horizontal and the vertical ...
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3answers
31 views

Polynomial Factorizations [closed]

Find the zeros of this function: $f(x) = x^2 - 3x - 40.$ My homework tells me to use a graphing calculator but I don't have one. How can I solve this w/o one? Thank you everyone for your help. I ...
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1answer
47 views

How do I graph acceleration?

I have written some java code for the calculation of some various acceleration and etc. type data. I am now trying to graph that data so I can pull specific data over a time line. The values I have ...
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1answer
16 views

parabola focal width

What is the focal width of the parabolic equation $y=x^2-8x-18$? I have pretty much all of the other vital numbers (vertex is $(4,-34)$, focus $(4, -\frac{87} 4$)) but am having a problem figuring ...
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0answers
23 views

Is my graph correct?

My problem told me that: Let $S$ be the surface described by the equation in cylindrical coordinates $z = r^2$, and the inequality $0 ≤ z ≤ 4$, oriented such that the unit normal vector points ...
3
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3answers
47 views

Equation of a … 3D object???

(Stupid question...) Well we can represent a point as something like $P(a,b,c)$ We can represent a line as $\dfrac{x-a}{p}=\dfrac{x-b}{q}=\dfrac{x-c}{r}$ We can also represent a plane as ...
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2answers
46 views

How to get the equation of this and plot it?

I was playing Mine Craft when I thought of this idea. first I mention some explanation : In this game there are creatures named villagers and also some named zombies. If a zombie hits a villager ...
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4answers
40 views

Formula for defining a curve

I am attempting to come up with a formula to describe something like the following: I need the curve to start from 90% on the left side and it needs to hit 0% at the five year mark on the right. ...
0
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2answers
24 views

Is there any software that can estimate a matching function for a set of plot points?

I have a set of 2D coordinates that represent a curve, and I'm struggling to find a function that roughly matches them. Is there any software (free, preferably) that can fairly accurately guess a ...
20
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1answer
1k views

What is the flaw in my thinking for the graph of this function?

Consider the map $$ f: \mathbb R^2 \to \mathbb R, (x,y) \mapsto x^3 + y^3 + xy$$ This defines a surface in $\mathbb R^3$. Let's consider some level set $f(x,y) = c$: (see here page 67) I think ...
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3answers
86 views

WolframAlpha wrong(?) graph

I had a question to plot a graph of $\space \space\LARGE y=x^{x^{x^{x^{...}}}}$ Which (according to me) is equivalent to $\large y=x^y \Rightarrow y^{\frac{1}{y}}=x$ So i plotted them in ...
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1answer
75 views

Why does the plot of the legendre symbol of $x^2 - y^2$ over a finite field look rectangular

The small top-left thing is a plot of the legendre symbol of $x^2 - y^2$ over $\Bbb F_{37}$. The thing in the middle is plot for $\Bbb F_{587}$. The thing on the right is a plot of the legendre ...
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0answers
30 views

Could someone explain to me why the range of the graph is R\(0,5]

I am trying to help my brother with his exam preparations, and we came across this question and found the answer a little confusing. Here is the graph and the range, taken from the answers page of the ...
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1answer
15 views

How to graph the intersection of two surfaces

Another way of asking this is: How would one graph a 1 dimensional line (the intersection) in a 3 dimensional space. Some context for the question: Let's say I have two spheres ...
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2answers
30 views

Graph the following system of inequalities

Graph the following system of inequalities. Show (by shading in) the feasible region. $$x+2y\leq 12$$ $$2x+y\leq 12$$ $$x\geq 0 , y \geq 0$$ I would like to know how to graph these ...
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0answers
32 views

following system of inequalities

Graph the following system of inequalities. $$x+2y\leq 12$$ $$2x+y\leq 12$$ $$x\geq 0 , y \geq 0$$ I just need to know how Can show the augmented matrix that describes the situation
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3answers
39 views

Graph and domain of $\frac{2}{7+\sqrt{x}}$

How to sketch the graph of $\frac{2}{7+\sqrt{x}}$? Can anyone give me some hints ?
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3answers
42 views

Rotate the graph of a function?

How do I rotate a graph of a function around a point, and show it in the related equation? An example could be $f(x)=\lvert x\rvert$ (absolute Value) and $f(x)=x^2$
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0answers
16 views

How to sketch this region in $3$ dimensions?

I need to sketch the following regions but I'm having major difficulty in doing so. Could anyone please help me. I don't want the full answer but want to learn how I can do it thanks. $$R=\{(x,y,z):0 ...
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6answers
131 views

Why do the equations $Ax + By + Cz= D$ represent planes in $\Bbb R^3$ and not lines?

I was wondering why $$Ax+By+Cz=D$$ represents a plane in $\mathbb{R}^3$, because from my perspective it seems that it could simply also represent a line in $\mathbb{R}^3$. And, yes, I do acknowledge ...