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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14 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
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3answers
49 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
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2answers
51 views

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

Can every one variable equation be solved without graphing? How would you solve the following without graphing: $$3y + 4\sqrt{1-y^2} = 2$$
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0answers
18 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
13 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)? ...
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0answers
36 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. ...
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0answers
14 views

Find the rule connecting $y$ and $x$ in the form $y=mx+c$ for $1<x≤2$ [on hold]

I have attempted numerous methods but I'm not sure how to interpret the $1<x≤2$ into a rule relating $y$ and $x$.
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3answers
54 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
votes
1answer
26 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 ...
1
vote
1answer
12 views

Can you stretch a function with a zero or undefined gradient?

If $y=f(x)$ is either $y=3$ (zero gradient) or $x=2$ (undefined gradient), is it possible to stretch $y=f(x)$ by graphing $y=af(x)$ or $y=f(ax)$? If it is possible to stretch them, can you only ...
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0answers
12 views

Can this implementation of the least squares regression be adapted for more precision? [closed]

I need some help to determine if a piece of VB code can be adapted. The code is as follows: ...
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0answers
10 views

Maximize Profit Math Problem [closed]

a small company produces hoodies and thermals and sells them through a chain of specialty stores. The company is to supply the store with a total of no more than 100 hoodies and thermals per day. The ...
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votes
1answer
30 views

Find inflection points of a function $f(x)=\frac{|x+3|}{\sqrt{x^2+1}}$

For $x\ge -3\Rightarrow f''(x)=\dfrac{3(2x^2-x-1)}{(x^2+1)^{\frac{5}{2}}}$ $2x^2-x-1=0$ for $x=-\frac{1}{2}\ge -3$ and $x=1\ge -3$ For $x< -3\Rightarrow ...
1
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0answers
37 views

How can I plot the complex function in 2D?

My function: $$sin(wt-jT) \tag{1}$$ where $j$ - complex unit, $T=0.1,\ w=8 \pi,\ t=[0,0.01,0.02..100]$ I transform it to function with real arguments: $$\sin(wt)\cosh(T)+j\cos(wt)\sinh(T) ...
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0answers
11 views

Function representing learning review graph

I've been working on this for a while but am unable to get it right. (If anyone is curious, I'm trying to make a model that determines a user's best time to review something that he has studied, this ...
1
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1answer
35 views

New SAT Math Section: Comparing Equation of Line to Graph

This is a math question on a practice test for the New SAT that will come out in March. These questions should not go above the level of precalc. I'm posting a picture of the problem as well because ...
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5answers
76 views

How to plot the graph of function $f(x) = \sqrt{8\sin^2x+4\cos^2x-8\sin{x}\cos{x}}$?

How to plot the graph of function $$f(x) = \sqrt{8\sin^2x+4\cos^2x-8\sin{x}\cos{x}}$$ Is it even possible ? When I tried it the function compressed into $$f(x) = 2\sqrt{\sin^2x-2\sin{x}\cos{x}+1}$$ ...
1
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1answer
26 views

Triple Simultaneous Equations not resolving the Equation for a Quadratic Function

so I'm doing this math problem for my Calculus I course in college. Here is a screenshot of the problem: Graph 1 (click here to view); the prompt is "Find an expression for the quadratic function ...
2
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1answer
44 views

What does the double vertical lines in the domain of a function mean?

In my math textbook there was a question to sketch a possible graph in which it gave me some information on it. One of the questions gave me the domain and range of the function. The domain was ...
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3answers
57 views

Is this quadratic pointing up or down? How do I know?

The equation is $-2x^2 + 4x + 30 = 0$. I simplified it to $-2(x^2 - 2x - 15)$. To know if it points up, I need to look at $ax^2$, and if $a > 0$ it is up and if $a$ is $< 0$ it is down. ...
1
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0answers
18 views

From current plot $y=f(x)$ get plot $dx/dy$ vs $y$

I have a plot $y = f(x)$ where $y$ is voltage and $x$ is capacity. Now I want get from this graph the $dx/dy$ vs $y$ plot. How can I get this new graph?
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1answer
30 views

The inequality used to study a trigonometric function's sign has no solutions

The function, sign of which we are asked to study, is: $$f(x) = 2\sin(x)\cos(x) - 1,$$ or, simplified: $$f(x) = \sin(2x)-1,$$ without using its graph to do so, since the exercise itself asks, in ...
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0answers
13 views

How to plot sinusoidal waves of color frequencies?

I'm looking for a function that I can use to plot a sinusoidal wave for various color frequencies. For example, the frequency of red light is 4.6 THz (4.6*10^14 Hz). The frequency of blue light is 6.3 ...
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votes
2answers
44 views

Complex Numbers: How do I know which plane to use?

I'm new to complex numbers and I want to know precisely when I need to use which plane for graphing and a general idea of what the plot would look like. $$z=a+bi$$ When it's in the form above, I ...
2
votes
1answer
29 views

Plotting the graph of $\operatorname{Re}(z)<2$

$$\operatorname{Re}(z)<2$$ My idea was that, in the complex plane, the graph looks like a ray starting at the origin and extending up to $2$, but not including that point. Then there would have to ...
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0answers
10 views

How can I obtain the equation of a complex signal such as ones obtained from analysing serial buses?

This is an example of a signal I would like to analyse For my mathematics internal assessment, I am trying to apply the Fourier Transform and put a signal through it in order to analyse it and ...
0
votes
1answer
21 views

Formula for a bent line

This may be simple, but I don't know the answer. I have the following data: (0,0) (1,12) (2,24) (3,30) (4,36) (5,42) (6,48) (7,54) and so on, the y coordinate increasing by 6 for values above 2 and ...
0
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1answer
24 views

Complex mapping problem and unsure if mistake in sheet

The following is based on the topic Complex Mapping. Example: Find the image of a straight line $2x + y = 1$ under the mapping $w = (1+i)z + 3i$. Solution: Let us rewrite the mapping ...
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1answer
33 views

Calculate curve using 3 points

I'm trying to find a way of creating a curve using 3 points in x,y space so I can use it to find other points. Essentially I have a unit which moves up and down on the y axis and I want to be able to ...
1
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1answer
39 views

Polar coordinates of an egg-shaped curve

For a simple 3D-rendering project, I need to get the shape of an egg. (actually, a prism with an egg-shaped based). The idea behind it is to explain how a camshaft in an engine is working. From ...
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2answers
32 views

Let $f:[1,\infty)\to R$ be a monotonic and differentiable function and $f(1)=1.$If $N$ is the number of solutions of $f(f(x))=\frac{1}{x^2-2x+2}$.

Let $f:[1,\infty)\to R$ be a monotonic and differentiable function and $f(1)=1.$If $N$ is the number of solutions of $f(f(x))=\frac{1}{x^2-2x+2}$.Find $N.$ ...
1
vote
3answers
28 views

How do you plot a graph where $y$ increases in short bursts and not linearly?

I am wondering if it's possible to plot this sort of graph with one equation. Note: the application of what I am doing is for video animation, but I am just asking for the mathematical ...
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2answers
43 views

Once I found the region, How can I found the Area

I have to find the area of the region bounded by $y = 4x^2$, the tangent line at $(3, 36)$ and the $x$-axis. I found the equation of the tangent line, which is: $y = 24x-36$ Both functions meet at ...
3
votes
2answers
35 views

What does this mean? (parabola)

The question is: If ($x,y$) represents a point on the graph of $y = 2x + 1$, which of the following could be a portion of the graph of the set of points ($x,y^2$)? The graphs are hard to put on ...
2
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1answer
45 views

Dynamical Systems: Finding Directions Around Equilibria?

I'm struggling to find the best way to determine directions about equilibria in order to draw a phase plot of this non linear dynamical system: $x' = x − xy,$ $y' = \dfrac{4}{5} − x^2 + x − y.$ By ...
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3answers
43 views

How do I graph Linear Programming questions?

So let's say I have the following constraints: $2a + 3b \leq 30$ $a + b \leq 15$ $a \geq 0$ $b \geq 0$ (I just made this problem up, so I'm not sure if it may make any sense when I graph it.) ...
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0answers
16 views

Suggestion for an interactive surface plot program?

I am looking for an interactive surface plot program, possible online and open source, to perform quick "visualisations" of 3d functions. For example, to plot function f=(xy) and then use the mouse ...
2
votes
4answers
93 views

Question about notation, language, and meaning in the context of combinatorics

In my math class today, my teacher defined a function as follows: A string on alphabet $[m]$ of length $n$ is a function: $$ s: [n] \rightarrow [m] $$ To seque back to math from programming, what ...
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0answers
21 views

rotation of spherical surface in spherical coordinates

I need to plot a spherical surface in computer (like the surface of a lens). I know the normal vector (as an example, say $\ n=(1,2,3) $) of this surface and it originates from the centre of the ...
4
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2answers
46 views

Draw the graph of $\sin(\pi/​2-​2x)$

I tried to draw the graph of this function $\sin\left(​\frac{\pi}{2}​ - ​2​x\right).$ If I understand correctly, this means that we have to shrink the graph by $2$, shift the curve by $\frac{\pi}{2}$ ...
0
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0answers
18 views

Is breaks in the continuity of a graph scalar with regards to multiplying a constant?

I think I'm probably right but seeing how I've recently begun to go down the rabbit hole in mathematics that tends to produce all sorts of inconsistenties with any advanced conjectures that I make, I ...
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3answers
37 views

What is the function of provided dataset?

x | y 0 | 0 1 | 1 2 | 1 3 | 2 4 | 2 5 | 2 6 | 3 7 | 3 8 | 3 9 | 3 10 | 4 11 | 4 12 | 4 13 | 4 14 | 4 15 | 5 16 | 5 17 | 5 18 | 5 19 | 5 20 | 5 Desmos ...
0
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0answers
9 views

Inserting “holes” on a graph.

I am trying to plot the set $A = \big\{(x,y) \in \mathbb{R}^{2} \mid x^{2} + y^{2} < 2 \big\} - \big\{(0,\frac{1}{n}) \mid n=1,2,3 \dots \big\}$. I have tried different combinations of set ...
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0answers
16 views

Function for this 3D curve

thanks for your attention. I am trying to plot a 3D surface like the picture below to help depict the relationship between some variables. I have been fiddling with Google Search builtin plotter, ...
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votes
1answer
51 views

How to analytically derive the geometric properties of a hyperbola and programatically use them to graph?

I have the following equation: $$ \left(10^{\left\lfloor\frac{\ln\sqrt k}{\ln10}\right\rfloor-1}+x\right) \left(10^{\left\lfloor\frac{\ln\sqrt k}{\ln10}\right\rfloor-1}+y\right) = k $$ Entering the ...
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0answers
41 views

Find an expression for the function which represents the bottom half of the parabola $x + (y-1)^2 = 0$

I can't seem to figure this question out. My workings are as follows: \begin{align*} x + (y-1)^2 & = 0\\ (y-1)^2 & = -x\\ y-1 & = \sqrt{-x}, \text{assuming that $x \leq 0$}\\ y & = ...
4
votes
1answer
36 views

Cis Graphs (Finding Values)

For this question: If you guys are not familiar with the $\operatorname{cis}$ notation $$ \operatorname{cis}(x) = (\cos(x) + i\sin(x)) $$ I've tried doing this: By comparing arguments $$ ...
0
votes
1answer
26 views

How would be the slope of $f(x)=y=ax$ where $x = \frac{a}{b}$?

Well, in physics we got $W = V\cdot I\cdot t \stackrel{R=^V/_I}{\Longrightarrow} \begin{cases} W = I^2\cdot R \cdot t \\ W = V^2\cdot \frac{1}{R}\cdot t \end{cases}$ In the first case the slope of ...
0
votes
1answer
47 views

X and Y intercepts

I have a function: $$y =\begin{cases} 3x, &\text{if } x ≠ 0; \\ 4, & \text{if } x = 0. \end{cases}$$ As I understand, function doesn't exist at (0;0). So, what ...