$$ \begin{align}x^2&amp;=x+x+\cdots\ (\text{$x$ times})\\ \implies \dfrac{\mathrm d}{\mathrm dx}(x^2)&amp;=\dfrac{\mathrm d}{\mathrm dx}(x)+\dfrac{\mathrm d}{\mathrm dx}(x)+\cdots \ (\text{$x$ times})\\ \implies 2x&amp;=1+ 1+\cdots \ (\text{$x$ times})\\ \implies 2x&amp;= x \\ \implies 2&amp;=1 \end{align}  $$  Which is obviously wrong. So, where am I wrong?
Consider the following:   $1 = 1^2$ $2 + 2 = 2^2$ $3 + 3 + 3 = 3^2$   Therefore,   $\underbrace{x + x + x + \ldots + x}_{x \textrm{ times}}= x^2$   Take the derivative of lhs and rhs and we get:   $\underbrace{1 + 1 + 1 + \ldots + 1}_{x \textrm{ times}} = 2x$   Which simplifies to:   $x = 2x$   and hence    $1 = 2$.     Clearly something is wrong but I am unable pinpoint my mistake.
What is the process for a moderator to request reinstatement or appeal a removal? Please leave any feedback or questions about this process on .   From time to time, moderators will step down or be removed from their positions — they may have expressed their wish to step down due to time constraints or they may have had behaviors unfitting of a moderator and have been forcefully removed, along with a number of other possibilities that fall somewhere between those two. What is the process for evaluating moderator reinstatement or removal appeal requests?  Note: Feedback on the original version of this post can still be found . Debian 10 systemd, how to disable autostart of graphical environments I installed a graphical environment on a server and I have decided that I no longer want to run that environment at boot. How can I disable it with systemd? This is gnome desktop environment. 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