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

learn more… | top users | synonyms (2)

0
votes
0answers
9 views

Labeling of axes in quotient space

It seems to be trivial, but I couldn't find anything. I have a metric space, let us say $\mathbb{R}^3$, and a equivalence relation $\sim$, let's say $(x_1,y_1,z_1)\sim(x_2,y_2,z_2)$ if $z_1=z_2$ and ...
1
vote
1answer
30 views

Identifying the formula for a quartic graphic

I am attempting to help someone with their homework and these concepts are a bit above me. I apologize for the terrible graph drawing. I am using a surface pro 3 and it has an awful camera so I can't ...
-1
votes
2answers
33 views

Need help to understand a math task about algebraic and parametric equations

Can anybody please explain this for me?: Find the algebraic and parametric equations of the circle with centre (-2,3) that passes through (1,-1) How do I find the algebraic and parametric ...
2
votes
2answers
49 views

Sketch the complex function: $z\overline{z}+(1+2i)z+(1-2i)+1=0$

Tried sketching the complex function: $z\overline{z}+(1+2i)z+(1-2i)+1=0$ I first simplified it by converting $z=x+yi$ I got: $(x+yi)(x-yi)+(1+2i)(x+yi)+(1-2i)+1=0$ Which gave me this implicit ...
0
votes
0answers
13 views

What's the best open source software for converting plots into Math functions?

I need to complete a year 12 Math homework which involves choosing an object with axial symmetry, plotting its side view on a piece of paper, integrating the resulting curve (assuming a 3D object is ...
0
votes
4answers
52 views

Tool to draw graphs when input points are given

I am writing a dissertation and I have a two collections of data from my research which I would like to compare using graphs. I have the values for abscissa and ordinate and I am looking for some sort ...
2
votes
2answers
61 views

Vector Functions of One Variable

Question A particle moves along the curve of the intersection of the cylinders $y=-x^2$ and $z=x^2$ in the direction in which $x$ increases. (All distances are in cm.) At the instant when the ...
3
votes
3answers
62 views

Geometric interpretation of inverse complex function?

Function $f\colon\mathbb{R}\to\mathbb{R}$ and its inverse $f^{-1}$ are symmetric over line $y=x$. It's easy to imagine inverse of real function, we just have to "flip" the plot over $y=x$. But what ...
0
votes
1answer
32 views

How do I solve this limit

**Find the limit ${x \to 6}$ if $ f(f(x))$ ** Any idea how to solve this graphical question on limits?
1
vote
1answer
22 views

Sketching a Graph of a Particle Trajectory

How can I sketch the trajectory of a particle of mass $m$ with a position vector $\mathbf{r} = \cos(\omega t)\,\hat{\mathbf{i}} + \sin(3\omega t)\,\hat{\mathbf{j}}$ ? Will this be a three ...
1
vote
0answers
58 views

Does anyone recognize this graph?

It's a plot of the following: Let $$f_{(n)} = \frac{np_n}{(p_1 + \ldots + p_n)}$$ so that $$g_{(n)} = \left|\space f_{(n)} - f_{(n-k)}\right| $$ where $n > k$ and $k = 5$ in this example. For ...
0
votes
2answers
78 views

How to get polynom formula from drawing?

I would like to have an analytic formula for certain functions that I can draw with a pen. For example, if I want a function like that then I can model it with the function $$ V(x) = (x-a)^2 ...
2
votes
1answer
28 views

Confusion with Heaviside Step Function and Ramp Function.

I want to know how to represent the following graph with Heaviside step functions and ramp functions. My guess is that this is represented as $r(t) -r(t-2) +2u(t-2)$, where $r(t)$ is the unit ramp ...
0
votes
1answer
16 views

Plotting a convex optimization problem

I have an optimization problem like below: $\text{minimize } - \sum_k w_k \log r_k$ $ a \leq r_k \leq b_k, k = 1, \cdots, 10$ Here, $w $ and $b$ is a set of constant: $w = [w_1, \cdots, w_{10}]$ ...
0
votes
2answers
42 views

reflecting a function about a line

Say you have a function $f(x)$ and a line $g(x)=ax+b$. How do you reflect $f$ about $g$? I am apparently supposed to write more text, but the line above is all I am after, hence I wrote this sentence ...
-2
votes
2answers
31 views

specifying an asymptotic function

Please help me out; I need to specify a function satisfying these conditions: $$ f(0)=1 \;\;;\;\lim_{x \to \infty}f(x)=0$$ Hopefully does there exist a simple answer? Thanks a lot!
0
votes
1answer
34 views

When does function $(\log_b(x))^p$ change its curvature?

Consider $(\log_b(x))^p$ where $b$ is a constant $>1$; $x, p \in \mathbb R_+$. As we increase the value of $p$ (starting from 1), at specific value of $p$, the curve changes its shape from ...
3
votes
0answers
14 views

How does emergent oscillation appear in this animation of concentric circles?

I made this animation and I barely understand it. http://bl.ocks.org/tophtucker/500d2a010105cfcc87db It's a bunch of concentric circles with exclusion compositing. The radius of the ...
1
vote
1answer
60 views

Converting $x^y-y^x=1$ Into $y=$ Form

This is probably going to be a simple answer, but, how would you convert $x^y-y^x=1$ into $y=$ form without any $y$ on the opposite side of the equation?
0
votes
2answers
28 views

drawing square root of an unknown function with a double root.

Without the equation of the function $y=f(x)$ and only the diagram, how would you draw $y=\sqrt{f(x)}$ and why? I am most interested in root if it looks like a double root but not necessarily a ...
0
votes
0answers
33 views

What is this curve?

A quick question. I have the following plot: Just looking at the coloured band where it transitions from red to blue, it looks like a function I have seen somewhere before (rotated 90deg ...
1
vote
2answers
48 views

Is the function $\ln(ax + b)$ increasing/decreasing, concave/convex?

$h(x) = \ln(ax + b)$ NB. Examine your results acccording to values of $(a,b)$ I've differentiated twice in order to get the following: $$ h''(x) = -\frac{a^2}{(ax+b)^2} $$ I think this proves ...
1
vote
1answer
50 views

Is the count for graphing trigonometric functions always 1/4 of a period? [closed]

I saw this video in YouTube since I'm studying for a quiz and found out that the count used for graphing trigonometric functions is 1/4 of a period. Is it always like that?? Sine, cosine, tangent, ...
-1
votes
1answer
31 views

How would I plot this function for all values of X,Y? [closed]

I have this function which I wish to plot: $y=b(a-x)^{8/25}$ I have the values for $x,y$ as part of a data set, with thousands of values. This is in a file. What i have found is that $x$ is between ...
2
votes
2answers
36 views

$6x -3y -18 =0$ What does $x$ and $y$ equal on a straight line graph?

I need to sketch a graph of $6x-3y-18=0$. I don't know if I'm on the right track but this is what I tried to get $x$: $6x-3y-18=0$ $\Rightarrow 6x-3y+18=0+18$ $\Rightarrow 6x-3y=18$ $\Rightarrow ...
-2
votes
1answer
21 views

Finding the horizontal asymptotes of a function

Here is the function I am trying to find the horizontal asymptotes for: $y=\frac{1-2^x}{1+2^x}$ Could you please explain how the horizontal asymptotes can be found for this function? Thanks.
0
votes
3answers
27 views

If the coefficients of the y-terms are equal and the coefficients of the x-terms are equal, the graphs of the two lines will be parallel.

So a student has a claim that for any pair of linear relations, if the coefficients of the y-terms are equal and the coefficients of the x-terms are equal, the graphs of the two lines will be ...
0
votes
0answers
19 views

Plot zeroes of polyomial in $\mathbb{R}[x,y,z]$ in Linux

I have a polynomial in $\mathbb{R}[x,y,z]$, say $$p_c(x,y,z)=x^2+y^2+z^2-xyz-c.$$ Do you know any simple piece of software to plot the zeroes of this polynomial using Linux? In the past I plotted ...
0
votes
0answers
19 views

Let T be the resultant BFS tree. If (u,v) is an edge of G that is not in T, then which one of the following CANNOT be the value of d(u)−d(v)?

This is MCQ of a competitive exam (GATE) , answer is option (d) given by GATE . I found explanation for (d) . With the commonsense or guessing the will be option (d) generally , I have doubt "Is given ...
-3
votes
1answer
19 views

Scale Proportionally a Polynomial [closed]

I have 3 polynomial functions that all overlap (to form a shape): I need to scale the polynomials down to half the current size. How do I do this? It must be scaled down proportionally ($x$ and ...
0
votes
2answers
46 views

Write a linear equation that represents this scenario.

Emma is planning her summer and would like to work enough to travel and buy a new laptop. She can earn 90 dollars each day, after deductions, and she can work a maximum of 40 days in July and August, ...
1
vote
0answers
13 views

parsimonious definition of a zig-zag function between two bounds

Suppose I have some strictly increasing function $f:[0,b]\to[0,b]$ with $0<b<1$, $f(x)<x$ and $f'(b)=\frac{1-f(b)}{1-b}$ (i.e. tangent to the secant line to $(1,1)$). Now imagine a 'tunnel' ...
2
votes
1answer
30 views

Is there a better way to represent the following formula?

A student has developed a money-saving strategy that uses the formula S = 450 + 100r . a) Give a possible interpretation of his strategy. I don't really know if my initial interpretation really ...
1
vote
1answer
36 views

$\sin^{-1}(\frac{2x}{1+x^2})+px=0$ has exactly 3 solution

If the set of values of $p$ for which the equation $\sin^{-1}(\frac{2x}{1+x^2})+px=0$ has exactly 3 solution is $(l,m)$.Then what is $2m-l$? ...
1
vote
3answers
61 views

How to sketch a surface in a three-dimensional space?

I was asked to hand sketch the surface defined by $$x^2+y^2-z^2=1$$ How could I do that? I find it particularly hard to draw graph in three-dimension, could you give me some advice?
1
vote
1answer
36 views

Determine the domain and range of the following relations using set builder notation.

I think I am starting to get the hang of using set builder notation, but I'm getting confused with the end points of these two specific questions. The blue text is hat I have already, but it would ...
0
votes
1answer
10 views

Comparing a function and its estimate

What are some clever ways of comparing (visually) a function with its estimate? For regions where the function does not cross zero, plotting the ratio of the functions and plotting the relative error ...
1
vote
1answer
17 views

Drawing ellipsoid with tanh

The function $f(x,y)=\tanh(R-\sqrt{x^2+y^2})$ for a given $R>0$ draws a circle with radius R with maximum and minimum of +1 and -1. This I can see when I plot ...
0
votes
0answers
19 views

How to find the formula of a function from its graph?

I've got some data points (X/Y coordinates) that were apparently created using a certain formula that I want to reconstruct now. I've only got those points, and I can plot them (e.g. like in this). I ...
2
votes
1answer
29 views

Does this graph represent a linear function?

a) Does this graph represent a linear function? Since this function does not graph to a straight line like linear functions do, does that make it not represent a linear function? b) What is ...
0
votes
0answers
26 views

State the domain and range of the following graphs.

State the domain and range of the following graphs. Express each domain using interval notation and express each range using set-builder notation. I think I'm beginning to understand using interval ...
0
votes
1answer
13 views

On determining a function given a certain parametrization of a point

Imagine we have a parametrization of a particle in 2D space like this http://i.minus.com/iXL64EfdJe6w5.gif How do we go about finding an explicit way to express these functions ($f(x)$ and $g(x)$) ...
4
votes
2answers
64 views

Why is there a discontinuity at zero?

For the function $$y = \frac{2x^2}{x-3},$$ I understand that $x = 3$ and $y = 2x+6$ are asymptote, but according to the answers in my textbook, there is a discontinuity at the origin. Why is this?
2
votes
3answers
90 views

Consider the function f(x)=sin(x) in the interval x=[π/4,7π/4]. The number and location(s) of the local minima of this function are?

This is MCQ of a competitive exam(GATE), Answer is (d) given by GATE , and from other sources ,explanation is (b) somewhere and (d) somewhere , I am going with (b) as minimum at $270$, I have drawn ...
0
votes
1answer
12 views

rectangular paddock, dimensions, maximise area it encloses

Having trouble trying to work out a question which involves finding a function to graph evidence of the correct answer, any advice would be greatly appreciated. I am struggling with part 'b' a lot, ...
0
votes
1answer
33 views

functions that jump from zero to value k and then decay back to zero

I am looking for functions that are zero for all $x< a$ and then from a suddenly jump to a specified value $K$ and then drop back to zero either quickly or slowly and perhaps even not necessarily ...
0
votes
0answers
29 views

Functon fitting goes wrong

Let's say I got a some function (let's say it named $B_w$) and I make a curve deped on some parameters. As example ...
3
votes
0answers
32 views

Plotting a 4D Dynamical System

Suppose I have a 4D dynamical system. Each axis has a fixed point, and there are orbits connecting the fixed points. It looks something like this: Each $Q_i$ is a fixed point on each axis of a ...
0
votes
0answers
13 views

creating smooth 2d plot with only a scaled colorvector and (x,y) coordinates | (matlab plotting issue)

I've an issue with visualizing the data in a correct way. I have an array with 3 colums and N rows. ...
0
votes
0answers
17 views

How to plot log poisson curve

Given number of failures per time interval is it possible to plot a log-poisson curve? If yes, can someone guide me.