How to upgrade from12.10 now that 13.04 is EOL?
How will people upgrade from 12.10 to later releases after 13.04 is EOL?
Disk Utility won't Unmount HD for formatting I want to prove that $\lim_{(x,y)\to (0,0)} \frac{\sin(x+y)}{x+y} = 1$  Is it sufficient to say that if $u = x+y$ then as $(x,y) \rightarrow (0,0)$ then $u \rightarrow 0$ and then evaluate $\lim_{u\to 0} \frac{\sin u}{u}$ which is 1 by L'Hôpital's rule?  I feel that this is somehow "cheating" and I would really like to prove it in a more rigorous way, i.e., by using an $\epsilon$ - $\delta$ argument.  I have tried for a long time to use the one variable version and prove that if $0 \lt \sqrt{x^2 + y^2} \lt \delta$ then somehow $0 \lt |x+y| \lt \delta$ and it would follow from the one variable case that $| \frac{\sin(x+y)}{x+y} - 1| \lt \epsilon$. However, because $|x+y| = 0$ when $y = -x$ I am not getting anywhere with this.  Any input on this would be helpful :) How to correctly install libpng12-0 on the Ubuntu 19.10? Let f be an r-cycle in $S_n$. Given any $h \in S_n$, show that $hfh^{-1} = (h(x_1), h(x_2), \dots, h(x_r))$ What equipment and settings do I use for panning shots of moving objects? How to show $f=g$ almost everywhere  Let two real-valued measurable functions $f$ and $g$ be such that for any measurable set $E$ the integrals $\int_E f\,d\mu$  and  $\int_E g\,d\mu$ coincide.  Could you please help.  It seems obvious. we could define the integrals as charges. can we do sth from here. but I do not know how to approach. Very hot network questions found Subclassing tuple with multiple __init__ arguments How long was Luke Skywalker's training with Yoda? From the answer to the question  :     We also don't know how much time Luke spent training.   I tried to check some references like  and  related section on their Wookieepedia articles, but there is not even a clue of the amount of time he spent there.  Is there any canon information on the subject? Or any extrapolation of how long Luke's journey on Dagobah was? Was it a day? Several weeks? Some months? Erf as term for plot of land in a town or city. Is this word only used in southern Africa? To evaluate limit of sequence $\left(\left( 1 + \frac1n \right) \left( 1 + \frac2n \right)\cdots\left( 1 + \frac nn \right) \right)^{1/n}$ How do I evaluate the limit of the following sequence $$a_n  = \left(\left( 1 + \frac1n \right) \left( 1 + \frac2n \right)\cdots\left( 1 + \frac nn \right) \right)^{1/n}$$   I tried to take log and then using cauchy $1^{st}$ theorem of limits but I coudn't do it.  Could someone kindly help? Until I went to army, I (had been / used to be / was ) a introverted person. - which one is right? Until I went into the army, I (had been / used to be / was ) an introverted person. And after I I finished army service, I became more confident.   I think all of these are possible.  As for had been, I'm referring to the state of me being introverted before the accident that happened in the past. So, I think I can use had been.  And at the same time I feel I can use used to be and was.. If I don't want to emphasize the time gap between two accident, I feel I don't need to use past perfect. So I think this problem depends on how I'm going to say something.   which one is preferable? and what is the difference? Prove $\int_0^\infty \frac{\sin^4x}{x^4}dx = \frac{\pi}{3}$ I need to show that  $$ \int_0^\infty \frac{\sin^4x}{x^4}dx = \frac{\pi}{3} $$  I have already derived the result $\int_0^\infty \frac{\sin^2x}{x^2} = \frac{\pi}{2}$ using complex analysis, a result which I am supposed to start from.  Using a change of variable $ x \mapsto 2x $ :  $$ \int_0^\infty \frac{\sin^2(2x)}{x^2}dx = \pi $$  Now using the identity $\sin^2(2x) = 4\sin^2x - 4\sin^4x $, we obtain  $$ \int_0^\infty \frac{\sin^2x - \sin^4x}{x^2}dx = \frac{\pi}{4} $$ $$ \frac{\pi}{2} - \int_0^\infty \frac{\sin^4x}{x^2}dx = \frac{\pi}{4} $$ $$ \int_0^\infty \frac{\sin^4x}{x^2}dx = \frac{\pi}{4} $$  But I am now at a loss as to how to make $x^4$ appear at the denominator.  Any ideas appreciated.  Important: I must start from $ \int_0^\infty \frac{\sin^2x}{x^2}dx $, and use the change of variable and identity mentioned above Disclaimer Yes, I am fully aware that what I am asking about is totally stupid and that anyone who would wish to try such a thing in production code should be fired and/or shot.  I'm mainly looking to see if can be done. Now that that's out of the way, is there any way to access private class members in C++ from outside the class?  For example, is there any way to do this with pointer offsets? (Naive and otherwise non-production-ready techniques welcome) Update As noted in the comments, I asked this question because I wanted to write a blog post on over-encapsulation (and how it affects TDD).  I wanted to see if there was a way to say &quot;using private variables isn't a 100% reliable way to enforce encapsulation, even in C++.&quot;  At the end, I decided to focus more on how to solve the problem rather than why it's a problem, so I didn't feature some of the stuff brought up here as prominently as I had planned, but I still left a link. At any rate, if anyone's interested in how it came out, here it is:   (I suggest reading it before you decide that I'm crazy). Creating 3D model in QGIS? Can I create a 3D model in QGIS or is there some model for 3D city models? Usually, in Star Trek, when there's a timeline change, the indication is that the original timeline is gone and replaced with the new one.  In City on the Edge of Forever, Kirk makes a comment that if they don't get the timeline straight, that millions of people who never died before will die.  Much of the time travel in Trek created suspense by declaring a need to restore the original timeline.  It's already been discussed in other questions about how, in the new movie (simply titled Star Trek with no subtitle or series number) they were unable to restore the original timeline.  While some of this is open to interpretation, it seemed like in this instance, for the first time, in Trek, there was an alternate timeline that was seen as an alternate possibility - no reference was made to it replacing the original timeline.  In this movie, was there any reference to the original timeline still existing?  In this movie, was the original timeline still considered to be intact? How do I change login screen theme or background in Ubuntu 20.04? How can I change the Ubuntu 20.04 login screen theme or background?  In the previous version 19.10, I can change it from the CSS file under Yaru theme but now there is no CSS file. How to reduce the number of authors above >3 to 'First Author et al., (year)'? How to show that this group presentation is isomorphic to dihedral group? The group with the presentation $\langle a, b \mid a^2, b^2, (ab)^4\rangle$ seems like a dihedral group of order 8. But I fail to explain why. Could anyone show me how to prove it? How can I check the available version of a package in the repositories? How can I check the version of the available package in the Ubuntu repositories without installing it?