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

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1answer
60 views

Heap tree to Pennant forest

First time poster. I'm having trouble identifying the way to represent a heap tree as a pennant forest, I understand that each pennant is a subtree of the heap but When i looked at an example i simply ...
1
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1answer
46 views

Find a sine function that intersects at ($y = 0$) for a given $x$

If (for say, visual aesthetics) I would like to plot the graph of a sine wave on a 2D graph that intersects the $x$ axis with value of $y =0$ when $x$ is some arbitrary integer - how would I go about ...
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0answers
24 views

Pressure-Temperature water diagram phase function

I'm trying to find a analytical expression that describes the pressure-temperature function. The function that I want to describe is the pressure-temperature function where the water is in liquid ...
0
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1answer
33 views

Finding Distance between two coordinates

I am a computer guy, I am making some simulations and try to figure out something. But there is some thing mathematical which I am not able to figure out. This is my whole area of ...
0
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1answer
30 views

Graphs of functions with arcsin and arccos

I know that to graph $\arcsin x$, I need to only take into account its principal values, that is its image is restricted to $[-\frac{\pi}{2},\frac{\pi}{2}]$. Same with $\arccos x$, its image is ...
3
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1answer
40 views

Extracting information from the graph of a polynomial

Problem: Below is the graph of a polynomial with real coefficients What can you say about the degree of the polynomial and about the sign of the first three and last three coefficients when written ...
2
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2answers
46 views

What is the maximum number of persons that may have shaken hands with everyone?

Hi. I am unsure about this question - I have answered n - 1, as we know one of the person dosen't shake hands.
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0answers
31 views

Symmetry in graphs of polynomials

I am learning graph skectching. Its well known that quadratic polynomials over reals are symmetric about their minima/maxima. But today I discovered an interesting result that Cubic polynomials are ...
0
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1answer
73 views

Is wolframalpha wrong (Plotting inequalities)

I just wanted to plot a simple inequality: $$-x \geq 4$$ and wolframalpha gives me the following plot: But I think it should look like this: Am I correct? If so why is wolframalpha producing such ...
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2answers
39 views

How do I graph these curves?

My teacher taught me this in class but I still don't understand it. Could someone please explain how to graph $y= x +\frac1x$ and $y = x - \frac1x$? Thank you :)
1
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1answer
31 views

Infinite sum of discrete unit-step signals

Trying to sketch the following signal: $$\sum_{k=-\infty}^\infty (u[k]-u[k-3])(u[n-k]-u[n-k-3])$$ Where $u[n]$ is the unit step signal (the Heaviside function, $1$ when $n\ge 0$ and $0$ otherwise). ...
3
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2answers
77 views

What does a graph of “A 7th degree polynomial equation with 4 imaginary roots” look like?

The question is "Draw a graph that possibly represents the following situation: A 7th degree polynomial equation with 4 imaginary roots." How would I draw this graph?
1
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1answer
31 views

How to plot the equation$x(x^2-1)^\frac{1}{3}$?

I would like to plot the function $x(x^2-1)^\frac{1}{3}$. When I do it in a statistical computing package, I dont get anything between $-1$ and $1$. However, when I plot this on google, I get a ...
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2answers
53 views

Find all real solutions: $36x^3 + 6x^2 = 9x$

I am having trouble finding all the real solutions to this problem. I do not undertand how to solve it, and I have a test on Polynomials tomorrow. The problem is "Find all real solutions using your ...
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5answers
84 views

Is the area under this graph finite?

Given the graph of $y=\frac{1}{x}$, and assuming that we limit our graph to the first quadrant, i.e. $x≥0$ and $y≥0$ Is the area under the curve finite? If so, what is the maximum?
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0answers
19 views

Question regarding plotting 120,000 points uniformly using log scaling

I have a bit of a strange problem I can't seem to wrap my head around. I am developing a game for the phone as a home project, I have a data-set of 120,000 different 3D points which represent the ...
0
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1answer
23 views

Problem with converting rotation representations (quaternion, axis-angle, etc)

I have a computer device - a 3D pointer (Sensable Phantom Omni). It returns cartesian position (X,Y,Z) and orientation quaternion (x,y,z,w). Now I have a 3D visualization software (PyMOL) and I need ...
1
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1answer
42 views

Local max, min and point of inflection of $y= ax^3 + 3bx^2 + 3cx - d$

Suppose $$y= ax^3 + 3bx^2 + 3cx - d$$ has a local maximum at $P_1(x_1, y_1)$ and local minimum at $P_2(x_2, y_2)$. Prove that the point of inflection is the midpoint of $P_1P_2$. I would mention ...
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2answers
25 views

Graphing using derivatives

Sketch the graph of the following equation. Show steps of finding out critical numbers, intervals of increase and decrease, absolute maximum and minimum values and concavity. $$y= xe^{x^2}$$ I ...
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1answer
18 views

How do I find the angle in relation to a horizontal line?

Assuming I have a string of numbers as follow: $x_1 = 112.26$ $x_2 = 111.9419999$ $x_3 = 111.4540002$ $111.0100004$ $110.5565004$ $110.2940004$ $109.8075006$ $109.3955007$ $108.7385004$ How do I ...
0
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0answers
17 views

Which vertices are adjacent to other vertices in the following undirected graph

I am unsure about this example. It says: Vertices $A$ and $B$ are adjacent, and so are vertices $B$ and $C$. But I think $A$ and $D$ is also adjacent or do I miss something?
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1answer
110 views

Is this graph plot for real?

I came across this equation while surfing through the internet.Is this for real?If it is how is it done?
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1answer
51 views

Calculus: Sketching a graph that satisfies the following conditions

The following question is from our reviewer for our upcoming exams: $\ast$ 3. Sketch the graph of a function $f$ satisfying the following conditions: (i). $-5,-3,-2,-1,0$ and $2$ are the only ...
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0answers
13 views

How to handle $y=0$ values when using logarithmic $y$ scale?

Imagine as example the following 2d data: x = (1, 2, 3, 4, 5); y = (4, 3, 2, 1, 0); I know that $\log(0)=-\infty$ but somehow I would like to "make visible" also ...
0
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1answer
39 views

Equation of a curved line from a graph

I am trying to calculate an equation to represent the graph attached to this question. It's an extract from a take-off performance graph used in aviation. The second graph shows how it is used. The ...
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1answer
30 views

Average of cosine waves

What looks like the graph of the function $A=E[cos(\omega t)]$, where $E$ means "average" and $\omega$ is a random variable?
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2answers
41 views

How to find differentiation and integration of curves in general?

Graph of function $f(x)$ How do I go about finding integration and differentiation of curves like these which yield other curves?
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1answer
30 views

What is this graphed function with asymptotes at π/2 and -π/2?

I've come across this function with asymptotes at π/2 and -π/2, which crosses the axis at y=1. It doesn't seem to be polynomial or exponential—can anyone figure out what it is? The asymptotes and ...
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3answers
45 views

How to make a semicircle graph?

What is the formula to make a semicircle graph that is continuous? By continuous I mean like a sine or cos graph but shaped like semicircles one after the other. Thanks
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3answers
53 views

Find the Equation of [closed]

Hi, Can someone help me to find the equation of this graph.I can find equation of parabolas and cubics individually but don't know where should i start.I know This graph can go to the 3rd polynomial ...
1
vote
1answer
35 views

Homogeneity of $f(x,y) = \frac{3x^2y}{x^2+y^2}$

Regarding my previous question about the function $f(x,y)$ somebody claimed that $f(ax,ay)=af(x,y)$ is only true for "homogeneous" $x$ and $y$. Does anyone know what "homogeneous" means in this ...
0
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1answer
32 views

How to find $x$-intercept on TI-83/TI-84 calculator without having to set the bounds for each intercept?

Finding $y$-intercepts is very easy on a TI-83/TI-84 calculator. All you have to do is graph the function and use 2nd $\to$ ...
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0answers
71 views

The domain of $\frac{\ln x}{x}$.

I have to find the domain for $f(x) = \frac{\ln x}{x}$ Naturally, $x$ must be larger than $0$ and $x$ can't be $0$ so $x > 0$. But when I graphed the function, it has two "parts", one in the ...
-1
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1answer
50 views

CALCULUS: Sketching a function by given conditions [closed]

Pls help. I'm currently on a struggle with this calculus problem. Thanks in advance.
2
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3answers
38 views

The decision boundary found by your classifier?

Can someone please explain in terms of "How To" find the decision boundary found by your classifier? If I plot using Octave: plot(theta); I get nothing like I ...
0
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1answer
17 views

Graph of the same function represented differently?!

I'm taking pre-calculus classes - learning about functions, limits and that stuff right now - and I came to $y = \sin(\frac{1}{x})$. Google represents it like this: Google_graph_of_$y = ...
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0answers
25 views

Help with understanding when Log(z^k)=k Log(z) as well as drawing the function.

For the question I'm dealing with the property Log(z^k)=k*Log(z)in which I have to find the largest open set that this property is true when $k$ is a positive integer. I understand that this ...
1
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0answers
18 views

Determining function of Graph

Looking through some notes on numerical computation I came across the following graph: I know this is a longshot, but I'm not incredibly mathsy and would like to know what kind of a function this ...
2
votes
1answer
33 views

Drawing critical points together with a level curve

I would like some help sketching the critical points of a given function. The function $f$ is given by $f (x, y) = (\sin x + \sin y)^2$ for all $(x, y)$ in $\mathbb R^2$. The critical points we have ...
0
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2answers
38 views

Physics Velocity Correction

So, been up all night working on getting the velocity/angle of arrow simulations perfect. Running into an issue with the physics engine I'm using is ever so slightly off (probably a rounding issue) ...
0
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0answers
40 views

What would cause the following graph?

I was playing around with a graphing calculator (like you do) and found an interesting graph of $\frac{x}{2^x}$. I was curious if any natural phenomenon that cause a graph to look like that, or if ...
0
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0answers
26 views

Class Scatter Fitness Function Calculation

I get a fitness function for class scatter, the equation: Click here to see the Fitness Function Where : T = Transpose of Matrics Mi = class mean Mo = grand mean The equation is based from ...
0
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0answers
17 views

Transforming parts of functions

I have a function in the form: $$ \mathrm{e}^{-t\lambda} \cdot \left[t\lambda - {(t\lambda)^2 \over 2}\right] $$ If one were to plot this for say $\lambda = \frac{2}{3}$ and $t$ from $0$ to $20$, ...
2
votes
3answers
57 views

Can you inverse a funcion by rotating it?

In school i sometimes run on some excercises where you need to calculate something that has an inverse function in it but you cannot find the inverse and you need to work your way around it. I know ...
0
votes
2answers
54 views

Can every one variable equation be solved without graphing? [closed]

Can every one variable equation be solved without graphing? How would you solve the following without graphing: $$3y + 4\sqrt{1-y^2} = 2$$
0
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0answers
19 views

How to analyse data set

I have a data set from work I'm not sure how to analyse. We have a bunch of people we've contacted (about $1,000$) at a random time during a project they're conducting. That time is expressed as a ...
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1answer
15 views

Assigning functions with graphs easily

Can someone help me with assigning functions with corresponding graphs? How should one proceed to make it easily without a ton of calculations (this kind of exercise I need to do within 5 minutes)? ...
0
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1answer
55 views

Graph of $f(x,y) = \frac{3x^2 y}{x^2+y^2}$ near the origin

I am trying to graph the function $f : (x,y) \mapsto \frac{3x^2 y}{x^2+y^2}$ on a TI-89 Titanium. I have noticed that no matter how many times I zoom in toward the origin the graph appears identical. ...
0
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3answers
56 views

Show that $\frac{1}{1+k}=\frac{\frac{1}{k}}{1+\frac{1}{k}}\leq \ln(1+\frac{1}{k})\leq\frac{1}{k}$

Prove the following: $$\frac{1}{1+k}=\frac{\frac{1}{k}}{1+\frac{1}{k}}\leq \ln(1+\frac{1}{k})\leq\frac{1}{k}$$ I know I can prove it with induction if the values were naturals. However, the "problem" ...
0
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1answer
30 views

Geometric Meaning behind the algorithm (slope of the line + ray casting)

I'm trying to dissect the classic algorithm for finding if a point is inside a (simple) polygon. Please see: http://erich.realtimerendering.com/ptinpoly/ and ...