Hello colleagues, I have a seminar that i need to turn in a weeks day from now.
My professor listed the following questions, guidelines that I should lean on:
1) Is it possible to achieve a temperature bellow absolute zero (-273,15)
2) An ideal gas contracts linearly when decreasing...
Hello there. I'm having some problems with absolute values when they contain multiple "abs" operators and some other numbers outside the "abs"-es.
For example:
\left | x+2 \right | - \left | x \right | > 1
If i check it for the positive scenario, the result is true for all x-es.
x+2...
Homework Statement
Given function f(x,y) = 3x2 - 2xy + 2y
a) find the critical point(s) of f,
b) sketch the region R: the triangular region in the xy-plane with vertices (0,0) (0,6) and (3,6)
c) find the absolute maximum and absolute minimum of f over R
Homework Equations
The Attempt at a...
Homework Statement
-F is a continuous function on [0,1], so let ||f|| be the maximum value of |f| on [0,1]
a. Prove that for any number c we have ||cf|| = |c|\ast||f||
b. Prove that ||f + g|| \leq ||f|| + ||g||.
c. Prove that ||h - f|| \leq ||h - g|| + ||g - f||
Homework Equations
Based...
Are lx3l or lxl3 polynomials?
If not, what would be a good example of a cubic polynomial function (R \rightarrow R) that doesn't cover all real numbers in its codomain?
Homework Statement
Draw |z| on a complex plane, where z = -3+4i
Homework Equations
N/A
The Attempt at a Solution
[PLAIN]http://img530.imageshack.us/img530/1786/aaakr.jpg
Can anyone please tell me which answer is correct?
Both of them have a moduli of 5.
So should the circle...
Homework Statement
prove
|arctan(x)-arctan(y)| \leq |x-y|
The Attempt at a Solution
I tried separating cases:
1. both x and y are in the same quadrant;
2. x and y are not in the same quadrant;
3. x and y are zero (trivial);
4. either x or y is zero.
Now, i can see why each of these is...
how do you go about solving abs value inequalities with double variables when the abs value bars are on both the variables?
eg; |x| + or - |y| =, >, <, a
Homework Statement
prove that llal-lbll\leqla-bl
Homework Equations
Triangle inequality
lx+yl\leqlxl+lyl
The Attempt at a Solution
Let a=(a-b)+b
By using the triangle inequality we get
lal-lbl\leqla-bl
Then from here I am not sure what I can do. I would like to say on the left...
Homework Statement
Then find the area S of the region. (between the curves)
Homework Equations
A = \int_a^b f(x)-g(x) dxThe Attempt at a Solution
First I plotted both equations, determined the top and the bottom functions and found where they intersected (calculator).
Then I set up the...
Homework Statement
Calculate the following, expressing all results with uncertainties both in absolute and relative (percentage) form:
a) A + B
b) A x B
c) Asin(theta)
d) A^2 / Bcos(theta)
The relevant formula for the absolute uncertainty is below, but i have no idea how to...
My calc book rewrites this equation:
|y|=e^c|x|
As this:
y=\pm e^cx
But that doesn't really make any sense to me. I know I should understand why we're allowed to do that, but I don't. Could someone please try to explain it to me?
I really appreciate your help, thanks!
As Stephen Colbert pointed out
http://news.yahoo.com/s/time/08599202066700
Amendment XIV
http://en.wikipedia.org/wiki/Fourteenth_Amendment_to_the_United_States_Constitution
Emphasis mine.
Yet Scalia voted for corporate personhood.
Frankly, I don't know what to say. How did this...
If time requires movement in space time in order for change and hence time to occur then how does absolute zero in temperature effect time since no molecular or atomic movement is possible at such temperature?
Does vibration constitute movement that can affect time in relativistic terms?
Is it...
Homework Statement
l [3/(x-1)] - 5l < 4Homework Equations
The Attempt at a Solution
My 1st step was to make the inequality like this. -4 < 3/(x-1) - 5 < 4
and then i multiplied (x-1) to both left and right side and as well as to the 5.
but in the end, my result turns out to be...
Hello,
I am having difficulty solving the following integral:
\int^{\infty}_{-\infty}e{-(a|x|+ikx)}dx
I have tried to use an explicit form of the absolute, eg.
-(a|x|+ikx) = \left\{\stackrel{-(ik+a)x\ x>0} {-(ik-a)\ x<0}
Does this allow me to separate the integral into a sum of two...
Homework Statement
y= l sin x l < absolute value of sinx
Homework Equations
The Attempt at a Solution
y= l sin x l= sinx, if x>0
-sinx, if x< 0
0, if x=0
I get that part, but when i draw the graph I don't get it
Homework Statement
Solve (x+2)/(x+1) -2 < 0
Homework Equations
LCD: x + 1
The Attempt at a Solution
(x+2-2x-2)/(x+1) < 0
(-x )/(x+1) < 0
But somehow, I got the wrong answer. The answer is (4, 7]. But I don't know where I went wrong.
Homework Statement
For the function y= |x2-4x+3|
a. Sketch the function
b. Is the function continuous? Explain.
c. Is the function differentiable everywhere? explain
d. find gradient of curve at the point where x = 3/2
Homework Equations
chain rule, differentiating...
The...
Homework Statement
*Sorry I could not get the math symbols to work properly so I did it by hand. I hope this isn't too much trouble.
Prove:
| sqrt( x ) - sqrt( y ) | <= | sqrt ( x - y ) |
for x, y >= 0
Hint: Treat the cases x >= y and x <= y separately.
I am new to proofs and we can't use...
I know that in Newtonian mechanics an inertial frame of reference moves relative to absolute space. But why does Newtonian mechanics include the contention that two inertial reference frames move relative to each other?
It seems that if you have an absolute reference frame then there is no...
Excuse me for my english;
Decide for all the x so this works out; ((2x-7)/(x3+3))<(9/x)<=x²-5x+9
where "<=" is the same as "and =".
Having some troubles getting the right values between (9/x)<=x²-5x+9, but otherwise it's fine..
hope you can help me!
I solved this absolute value equation and I am confuse about the answer given in the book for this question, the answer in the book is x > = 0 or x = -2/3 please tell me how can I get this answer from the following solution. Please tell the method which should be true for all such type of...
Suppose we have this absolute value question | x-3 | = 3 – x
If we solve this question we break it as
X - 3 = 3 – x or -(x - 3) = 3 - x
Now if we solve it we come to know that the part on right is true for all real numbers
And the part on the left is true for only 3
I also have read that...
Homework Statement
Let X be a continuous random variable with median m.
Minimize E[|X - b|] as a function of b. Hint: Show that E[|X - b|] = E[|X - m|] + 2 \int (x - b) f(x) dx , where the integral is from b to m.
Homework Equations
The Attempt at a Solution
I wanted to try a...
I started posting to what seemed to be a related thread here:
https://www.physicsforums.com/showthread.php?p=2825641&posted=1#post2825641
After concluding I was hijacking another thread, I am posting here.
The concept is I think that, in theory, one can determine absolute speed. Am I the one...
Homework Statement
Solve the inequality and sketch the graph of the solution on the real number line.
Homework Equations
|x - a|< or equal to b, b > 0
Let us imagine that the ">" and "<" signs also include "equal to" except for the condition, b > 0, in order to solve this...
Homework Statement
I do not have a specific homework problem, but could someone please clarify this for me?
QUESTION: When you have an absolute maxima (or minima), how can you tell if it is ALSO a relative maxima (or minima)?
I understand how to find absolute extrema on a closed...
regarding the problem of time in QG,
Is time absolute or dynamical in LQG?
string theory?
How does LQG and string theory deal with time in singularities in the center of black holes?
Relativity says that there is no absolute simultaneity. Quantum mechanics with its entanglement seems to imply absolute simultaneity. And in between these two I am the one who gets confused. :smile: :confused:
Please Help.
Homework Statement
I have
E(a) = 0, E(b) = x but E(|a+b|)=??
where E is the expectations operator and x is a known constant which is greater than zero.
Homework Equations
Any one know how I would go about determining E(|a+b|)?
Hi,
With a meridian circle, you can determine the latitude of your location (Horrebow-Talcott method) but also deriving time if you know the right ascension of a star.
However, I'd like to know how to determine right ascension of a star with a meridian circle.
If you know the right...
Greetings,
I have heard that one can not know one's absolute velocity, only one's velocity relative to other objects.
But wouldn't the cosmic background radiation be blueshifted in the direction of motion and redshifted in the oposite direction?
Thanks
I've been thinking about getting a tattoo. I was considering getting the infinity symbol inside of an absolute value. Or the absolute value of infinity. Whichever you prefer.
How mathematically correct is that? The absolute value of infinity simplified is infinity is it not? Will I completely...
http://www.sciencedaily.com/releases/2010/06/100627072458.htm
According to the above article, light was brought to a complete stop during an experiment. What confuses me is that, if light has no mass, and is then manipulated to have no velocity either (which means there is no frequency and...
Homework Statement
I saw this in my real analysis textbook and I have been trying to understand how this equation \left | x-c \right |< 1
you can get this: \left | x \right |\leq \left | c \right | + 1
Homework Equations
I wanted to know what steps made this possible ...
I'm having trouble understanding angular momentum and how it relates to SR/GR. To keep it simple, if I'm in space and all matter and energy is removed (ie. reference frames) and I start rotating at a specific velocity will I feel my arms and legs being pulled out? If the only possible frame of...
Sorry if this question seems more philosophical than scientific. It's my first post in this forum. I love learning about the way the universe works and I always have lots of questions :-)
Alright, so to my point. It seems like the theory of relativity says that the faster you move (plus how...
Homework Statement
By comparing with the luminosity of the Sun, calculate the absolute magnitude of a 60W lightbulb. [THe absolute magnitude of the Sun is +4.75; you may ignore colour differences]
Homework Equations
m-M=5log(d/10pc)
f = \frac{L}{4\pi d^{2}}
m1 - m2 = -2.5long(f1 / f2)
The...
Homework Statement
If a,b are real numbers and b does not equal zero show that |a|=sqrt(a^2) and |a/b|=|a|/|b|.
Homework Equations
I know that |ab|=|a||b| and a^2 = |a|^2
The Attempt at a Solution
Attempt at showing that |a|=sqrt(a^2):
|a|=sqrt(a^2)
|a|^2=(sqrt(a^2))^2...
Hi,
I came across a book which looks at a problem like
\lim_{x \to 0}\frac{1}{x}
So you approach from 0-, and get -∞, approach from 0+, get ∞
Then it would write the answer as
\lim_{x \to 0}\frac{1}{x} = \left| \infty \right|
It looks bizarre to me. How do you parse this? Is...
Consider this thought experiment. Second postulate of SR (invariance of c) says that the speed of light is measured the same for all inertial observers regardless of their relative KE.
To better understand what that means I try to imagine how would that look from a perspective of the moving...
Homework Statement
how do I solve this? I am confused...
|2x - 1| = x^2
Homework Equations
The Attempt at a Solution
when i tried it I ended up with a solution set of (1,-1). But the official answer is quite different so I am confused!
"Absolute" light speed or velocity or both?
Consider an inverse of Einstein's light clock. On a cartesian plane in a vacuum, a beam of light emanates from the origin at 45 degrees with velocity c. Is it OK that the x and y component velocities are each less than c (i.e. c divided by sqrt 2)...