Prove that $0.\overline{9}= 1$
286
Is it true that $0.999999999\ldots=1$?
66451
In a ring, how do we prove that a * 0 = 0?
12402
Showing a function on $[0,1]$ is the zero function
23684
Prove for all integer $n > 1$ that if $n | 34$, then $n+5$ and $n^2+$9 are coprime
61472
If $0<x<y$, then prove that $\sqrt{x} <\sqrt{y}$ and $x <\sqrt{xy} <y$
15104
Show that $\big|\frac{a-b}{1-\overline{a}b}\big|=1$, when either $|a|=1$ or $|b|=1$.
27570
Prove $(1-x)\ln(1-x)+(1+x)\ln(1+x)\leq 2x^2$ for $0<x<1$
107842
Behaviour of ($\overline{a}_n)_{n=1}^{\infty}$ and ($\underline{a}_n)_{n=1}^{\infty}$
31766
Prove that $a_{n}=0$ for all $n$, if $\sum a_{kn}=0$ for all $k\geq 1$
7448
Prove $S \doteq \sum_{n=1}^{\infty} p_n  0$ assuming $0 \leq p_n < 1$.
59475
Show that $\sqrt{n+1}-\sqrt{n}\to0$
115145
Show that $n-m$ is a multiple of 9 when $n$ and $m$ have same digits
126989
Prove that $g(z)=\overline{f(z)}$ is complex diﬀerentiable at $a$ if and only if $f'(a) = 0$.
22869
Prove $[0, 1]$ and $(0, 1]$ are equinumerous by use of bijection
81822
How many integers between $1$ and $10^4$ contain exactly one $8$ and one $9$?
5526
Prove that $ℤ[i]^*= \{1,-1,i,-i\}$
67291
Prove that there exists $n\in\mathbb{N}$ such that $f^{(n)}$ has at least n+1 zeros on $(-1,1)$