Answer:
-[tex]\sqrt{3}[/tex]
Step-by-step explanation:
We know that cot (-x) = -cot x
therefore cot(-210) = -cot(210)
and we know that cot (180+x) = cot(x)
[since 210 lies in third quadrant therefore its positive ]
therefore cot(180+30 ) = cot 30
so here in the question
cot(-210) = -cot(210) = - cot (30)
= -[tex]\sqrt{3}[/tex]
