updates
Can two lines lying in different plane be parallel?
In two lines lie in different plane, can they be parallel to each other? I am thinking if two lines are parallel to each other, then their direction cosin...
Apr 16, 2026
Archive: Updates
updates
Verify Demorgan's Law Algebraically
If $\overline X \equiv \text { not }X$, De Morgan's Laws are stated as: $ \overline{(A + B)}= \overline A\cdot \overline B$ $ \overline{(A\cdot B)} =...
Apr 16, 2026
updates
Meaning of l.i.m.?
I've been reading Akhiezer's "The Classical Moment Problem" recently and came across the expression (in Chapter 2): $$f(u) = Ux = \operatorname*...
Apr 16, 2026
![How do I find the asymptote of $y= -\tan(x+\pi/4)$? [closed]](https://news.conceivablytech.com/uploads/how-do-i-find-the-asymptote-of-y-tan-x-pi-4-closed_720.jpg)
updates
How do I find the asymptote of $y= -\tan(x+\pi/4)$? [closed]
$$y= -\tan(x+\pi/4).$$ How do I find the asymptote of this?
Apr 16, 2026
updates
How to read Hatcher's Algebraic Topology?
I have to read Allen Hatcher's textbook and I am having a really hard time with the book. To cite examples, I find chapter 0 unreadable, especially t...
Apr 16, 2026
updates
Why use sine and cosine when resolving vectors into components?
I have always wondered why you have to use sine and cosine instead of a proportional relationship, such as $(90-\text{angle})/90$. I cannot seem to find a...
Apr 16, 2026
updates
How many different definitions of $e$ are there?
It seems as though, in my analysis and calculus courses, in particular, a common cop-out when asked to prove an identity involving $e$, is the phrase "it&...
Apr 16, 2026
updates
How people found or derived shortcuts for derivatives?
Maybe it is a soft question, I can't find any information about this. How people understood that we can use derivative shortcuts instead of calculati...
Apr 16, 2026
updates
The (standard) definition of a group.
Edited to incorporate suggestions from the comments and responses: Typically, the definition of a group is as follows: Definition: If $S$ is a set, $*$ is...
Apr 16, 2026
updates
Limit point versus limit and implications for convergence
I understand that similar questions to this have been asked here (1) and here (2) but I believe my question is different because with regards to (1) I am ...
Apr 16, 2026
