New posts in rational-numbers

Enumeration of rationals from Stein-Shakarchi's Real Analysis (Chapter 1, Exercise 24)

The "guess the number" game for arbitrary rational numbers?

Let $x^3+\frac{1}{x^3}$ and $x^4+\frac{1}{x^4}$ are rational numbers. Show that $x+\frac{1}{x}$ is rational.

Show that the numerator of $1+\frac12 +\frac13 +\cdots +\frac1{96}$ is divisible by $97$

Proving that $\sqrt{13+\sqrt{52}} - \sqrt{13}$ is irrational.

Are there infinitely many rational outputs for sin(x) and cos(x)?

Is it true that $\left(-\frac{1}{64}\right)^{-\frac 43}=256$? [duplicate]

Representation of positive rational numbers as series. [duplicate]

Convergence of $\sum_{n}\frac{q_n}{n}$, where $(q_n)$ enumerates $\mathbb{Q}\cap[0,1]$?

Why is $x^3-5x$ injective on the rationals?

Show that the set of polynomials with rational coefficients is countable.

Minimal $ab$ for Rational Number $a/b$ in an Interval

About the continuity of the function $f(x) = \sum\limits_k2^{-k}\mathbf 1_{q_k \leq x}$

Rational values of trigonometric functions

The set of rationals has the same cardinality as the set of integers

Niven’s theorem proof.

Remarkable/unexpected rational numbers

Orbits of vectors under the action of $\mathrm{GL}_n(\mathbb Q)$

Infinite number of rationals between any two reals.

Determine all functions satisfying $f\left ( f(x)^{2}y \right )=x^{3}f(xy)$