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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1
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1answer
8 views

Reading a graph with irregular intervals

This graph represents a large range along the x-axis, but I'm unsure how to read such a graph reliably. For instance, if I wanted to find 2 on the x-axis, what vertical line would I use, and more to ...
1
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1answer
17 views

Find formula structure for a complex function

I am looking to find the function formula structure of a repeating function like the one in the image linked below.... Something that repeats indefinitely (like a sine wave) on the X-axis. Anybody ...
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0answers
28 views
0
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0answers
33 views

How do I plot a function like this in cylindrical polar coordinates?

Considering that $R = (x^2 + y^2)^{1/2}$, $x = R\cos(\phi)$, $y = R\sin(\phi)$, plot: $$R(\phi) = \left(\dfrac{(\cos\phi)^{1/2} + (\sin\phi)^{1/2}}{ \cos\phi + \sin\phi}\right)^2$$ Have tried to ...
0
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2answers
131 views

Joining two graphs

Suppose I have $f_1(x)=x$ And i restrict its domain as $\color{blue}{(-\infty,0]}$ using $g_1(x)=\dfrac{x}{\frac{1}{2\left(x-0\right)}\left(x-0-\left|x-0\right|\right)}$ Resulting in : Now, ...
0
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0answers
18 views

Piecewise Logistic Function [Satellite Data]

I am working with $16$-day MODIS EVI (satellite) data and I want to fit a Piece-wise Logistic Function through my $23$ EVI data values. The following formula is for the Piece-wise Logistic Function: ...
3
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2answers
53 views

Plot of $y=x+0\sqrt{-x}$ (and WolframAlpha vs Desmos)

To plot the graph of $y=x+0\sqrt{-x}$ : Do we have to first find out the domain of $y$ which is $y \in ( -\infty,0 ]$ ? $\color{blue}{\text{[Case 1]}}$ (that's what I do) Or do we solve the ...
0
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1answer
14 views

Build function graph in 3d [on hold]

I don't understand how to build the following function graph: in each dimension i need to move through the circle with radius = 1, and get the result trajectory, but how to visualize it ? For example ...
1
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1answer
30 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 ...
1
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3answers
39 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
41 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 ...
3
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2answers
39 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?
24
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4answers
843 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
votes
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 ...
1
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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 ...
0
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0answers
41 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 ...
0
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1answer
21 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 ...
0
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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 ...
1
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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 ...
1
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1answer
37 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 ...
3
votes
6answers
504 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.
1
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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 ...
0
votes
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 ...
5
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0answers
84 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 ...
1
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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 ...
2
votes
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 ...
1
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0answers
22 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, ...
4
votes
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 ...
1
vote
3answers
40 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 ...
-4
votes
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 ...
0
votes
1answer
50 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 ...
1
vote
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 ...
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 ...
2
votes
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 ...
0
votes
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. ...
1
vote
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 ...
2
votes
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 ...
3
votes
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 ...
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 ...
0
votes
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 ...
1
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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 ...
8
votes
1answer
76 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 ...
1
vote
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 ...
0
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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
0
votes
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 ...
3
votes
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 ?
1
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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 $f(x)=x^2$
-1
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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 ...
4
votes
6answers
134 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 ...
1
vote
2answers
52 views

Why can't $x$ be negative in $x^{\ln{y}}$

According to wolfram alpha, the domain of $x^{\ln{y}}$ is $x>0$ and $y>0$ but putting $(-1,1)$ for $(x,y)$ I get a perfectly fine answer of 1? $y>0$ makes sense, since $\ln{y}$ is only ...