Is there a real number $x$, that the expressions $\tan x + \sqrt{3}$ and $\cot x+ \sqrt{3}$ are both integers?
My solution:
First, let's assume $\tan x + \sqrt{3}=a$ and $\cot x+ \sqrt{3}=b$ where $a,\,b$ are both integers.
From the second equality, we get:
$\cot x+ \sqrt{3}=b$
$\cot x=b-\sqrt{3}$
$\dfrac{1}{\tan x}=b-\sqrt{3}$
$\tan x=\dfrac{1}{b-\sqrt{3}}$
so we get
$\tan x=\dfrac{1}{b-\sqrt{3}}=a-\sqrt{3}$
$(a-\sqrt{3})(b-\sqrt{3})=1$
$\sqrt{3}=\dfrac{ab+2}{a+b}$
But recall that both $a,\,b$ are both integers, this last equality contradicts to our previous assumption and so the answer is nope.
There isn't any real x that serves both the given two expressions to be integers.
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