Suppose that the domain of the propositional function $P(x)$ consists of the integers -2, -1, 0, 1 and 2. Write out each of these propositions using disju...

I am graduating with a BA this summer and I am very interested in topology. I admit it, I never went that deep into topology and all I know is about point...

Find a general solution to $x^2-2y^2=1$ I found that (3,2) is a solution. Now what should I do? I can not catch what the question really want. It is about...

How can I prove that $xy\leq x^2+y^2$ for all $x,y\in\mathbb{R}$ ?

I am trying to find the fundamental period of $ f(x) =-6\cos(5\pi x)$. I know a periodic function satisfies $f(x)=f(x+p)$. I know that $\cos(x)$'s pe...

What is the proof of permutations of similar objects? I know the formula, but I cannot figure out how to derive it! permutations of similar objects The nu...

And what is the quickest way to solve this with a calculator?

How many weighings of a balance are necessary to determine if a coin is counterfeit among eight coins. The counterfeit coin is either heavier or lighter t...

I encountered this symbol in an old Adobe mathematical character set, and I'm trying to identify it. I can't find it on Wikipedia's list of...

In this set of online math notes the following is stipulated: $$\left(\sum_{n=0}^\infty a_n\right)\left(\sum_{n=0}^\infty b_n\right) =\sum_{n=0}^\infty (c...