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Trial Solutions for Differential Equations

I have a question from my Differential Equations & Linear Algebra class. When you're trying to find the general solution to an nth order linear n...

Published: Aug 30, 2026

general

what is the difference between ${10 \choose 2}$ and ${10 \choose 1}\times{9 \choose 1}$?

I'm not able to understand the difference between these two. Don't both just give the number of ways of selecting $2$ objects from a total of $1...

Published: Aug 30, 2026

general

How do I compute a double weighted average? In other words, an average with two weighting factors.

This might be a simple question... I was wondering, how does one take a double weighted average? (honestly, don't know if that is what it is called)....

Published: Aug 30, 2026

news

Expected number of coin flips to get three heads or three tails

We both play a game where we flip a coin. You win if 3 heads appear, I win if 3 tails appear. What is the expected number of flips for the game to end. Th...

Published: Aug 30, 2026

general

How are the known digits of $\pi$ guaranteed?

When discussing with my son a few of the many methods to calculate the digits of $\pi$ (15 yo school level), I realized that the methods I know more or le...

Published: Aug 30, 2026

updates

Proving a statement using the definition of a limit

Let $f$ be a function that is defined on a deleted neighbourhood of $x_0 ∈ \Bbb R$, such that $f(x) \ne 0$ for every $x$ on that deleted neighbourhood. Su...

Published: Aug 30, 2026

general

What is the measure of angle F?

This is an isosceles triangle with base angles being the only part filled in. I have trouble understanding that if the base angles are not like terms, the...

Published: Aug 30, 2026

news

Some tips on 3D Trig?

I understand this isn't a MATHS question specifically, however, sometimes I have trouble identifying when to use 3D trig, and trouble with it in gene...

Published: Aug 30, 2026

updates

What is an indexed set?

I stuck on something. I am trying to understand what is said in the image I linked above. "A function I from a set Λ onto a set a is said to index the set...

Published: Aug 30, 2026

news

Question on the 'Hat check' problem

The famous 'Hat Check Problem' goes like this, 'n' men enter the restaurant and put their hats at the reception. Each man gets a rando...

Published: Aug 30, 2026