New posts in algebra-precalculus

How much math do we need to prove all simple numeric identities?

How many solutions are there to $x+y+z=14$ where $x,y,z$ are all non-negative integers, $x \leq 5, y \leq 6, z \leq 7$?

If $\alpha + \beta + \gamma = \pi$, then $\cos^2 \alpha + \cos^2 \beta + \cos^2 \gamma + 2\cos \alpha \cos \beta \cos \gamma = 1$

Prove that the polynomial $f_n(x)=nx^{n+1}-(n+1)x^n+1$ is divisible by $(x-1)^2$

If $x^n=y^n$ and $n$ is odd then $x=y$

Every non-empty subset of the integers which is bounded above has a largest element.

The roots of $t^5+1$

Understanding the slope of a line as a rate of change

Find $x$ in the equation $ax^3+bx^2+cx=d$

Eliminate $\theta$ from $\sin3\theta=a\cos\theta$ and $\cos3\theta=b\sin\theta$

$\max(a,b)=\frac{a+b+|a-b|}{2}$ generalization

Proving that matrix in equation is invertible

How to prove or disprove $\forall x\in\Bbb{R}, \forall n\in\Bbb{N},n\gt 0\implies \lfloor\frac{\lfloor x\rfloor}{n}\rfloor=\lfloor\frac{x}{n}\rfloor$.

Solve $x^x=2x$ where $x\in\mathbb C$.

How to prove that the problem cannot be solved by the four Arithmetic Operations?

How $\frac{1}{n}\sum_{i=1}^n X_i^2 - \bar X^2 = \frac{\sum_{i=1}^n (X_i - \bar X)^2}{n}$

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

Circles generated by three-fold iterations $f(x)=\frac{1}{1-x}$

Dodecahedron and golden ratio algebra

Simplify the expression $\binom{n}{0}+\binom{n+1}{1}+\binom{n+2}{2}+\cdots +\binom{n+k}{k}$ [duplicate]