Thanks, in the absence of an answer I've reread my notes, and managed to solve the problem. I've had to put everything in it's place in my head(all the different accelerations, and velocities). English is obviously not my mother language so I probably got the terminology part wrong.
Homework Statement
A wheel is spinning at n=1200rpm. The wheel starts to linearly decelerate, and after t=100s it stops. Determine the velocity, and acceleration of a point 10cm from the center of the mass, after 50 seconds of decelerating. The radius of the wheel is 30cm.
Homework Equations...
Homework Statement
So I was wondering how do we account for vectors that are at a certain angle. The problem that I'm having with the picture is: if I was calculating torque from point B, how would I account for the vector G.
Homework Equations
The Attempt at a Solution
I've...
Homework Statement
Hello, I'm having a problem with this. So we drop the weight on this spring, and the question is: how much does the spring compress? The mass is 5kg, the height 0,4m, and the spring elasticity factor k=1700N/m.
Homework Equations
The Attempt at a Solution
I've...
Homework Statement
I'm having a problem with solving the domain of |x^2+y^2|<=|z^2|.
Homework Equations
The Attempt at a Solution
From what I got this should be separated into two expressions:
x^2+y^2<=z^2, and x^2+y^2>=-z^2. The later doesn't have a real solution because of the...
Homework Statement
So I need to determine if the series \Sigmaln(1+e^{-n})/n converges.
Homework Equations
The Attempt at a Solution
I know it does, but cannot prove it. Wolfram says that the ratio test indicates that the series converges, but when I try to solve the limit I get that it...
My textbook doesn't say it needs to be the absolute value, although it's under the absolute convergence chapter. When I think of it, it makes a lot of sense that it needs to be absolute convergence. But then again if we pair lim(n->inf)a_n=0 with a decreasing function I think we get the same thing.
Yes, that is what I meant. English is my second language so math terminology in English is not my strong point. That was my question, and thanks for clearing it up!
Homework Statement
Hello, I was wondering if a falling function needs to fall on it's whole domain? I was solving a series with alternating sings. It says that if the series has alternating signs, that it converges if:
1) lim(n->0)an=0
2) an is a falling function
I was solving this...
Homework Statement
I've been trying to integrate the following: ∫\frac{cos^3(x)}{\sqrt{sin(x)}}dx
Homework Equations
The Attempt at a Solution
First, I substituted sin(x) with t, and got dt=cos(x)dx => dx=\frac{dt}{cos(x)}.
After that I got ∫\frac{cos^2(x)}{\sqrt{t}}dt
Then i transformed...
From all this my guess will be 1, but still not clear why. Is it because lim x->0 means that x !=0 but rather close to 0? Meaning some infinitesimal number ^0=1? Am i getting that correctly?
Homework Statement
I've read in my textbook, and confirmed via WolframAlpha that lim x->0 (cosx/x^0) =1 , and need an explanation for it. I thought it should be ∞ or something undefined, since 0^0 is undefined.
Homework Equations
The Attempt at a Solution
I tried to use L'Hospitale on the...
Thank you very much eumyang and LCKurtz! This really helps a lot. Now i realize that i have to look at it as a whole, and not two separate inequations. I don't know if there's some repping system on this forum but you definitively get my thanks/+1
I did take that in account, and made 2 scenarios (unlike the example):
1.positive or zero/positive
2.negative or zero/negative
In the first case i get <-inf,-2]U[3,+inf>
and <7,+inf> !!
In the second case i get [-2,3] !!
and <-inf,9>
So how do i get half the right answer in 2...
Could you explain why? I understand the lower part, but the quadratic inequation bothers me. The first index is a>0 => parabola with a minimum vertex, meaning it's values are >=0 from <-inf,-2]U[3,+inf>. That is the reason i made this thread.
Homework Statement
Hello! Could someone explain some things presented in this example: http://i.imgur.com/wVOxf.png
My friend, and I haven't been able to crack it. I get all the x-conditions right, but can't put the whole thing together into a domain. Here it's presented that xe[-2,3] due to...