#### Answer

$\dfrac{\pi}{4} \leq \theta \leq \dfrac{3\pi}{4}$ and $0\leq r\leq \csc \theta$

#### Work Step by Step

Conversion of polar coordinates and Cartesian coordinates are as follows:
a)$r^2=x^2+y^2 \implies r=\sqrt {x^2+y^2}$
b) $\tan \theta =\dfrac{y}{x} \implies \theta =\tan^{-1} (\dfrac{y}{x})$
c) $x=r \cos \theta$
d) $y=r \sin \theta$
As $y=r \cos \theta =1\implies r=\csc \theta$
Therefore, the region described in polar coordinates is:
$\dfrac{\pi}{4} \leq \theta \leq \dfrac{3\pi}{4}$ and $0\leq r\leq \csc \theta$