Answer
(a) $θ=60°=\frac{\pi}{3}rad$
(b) $θ=45°=\frac{\pi}{4}rad$
Work Step by Step
Consult the table on page 436:
(a) $θ=60°=\frac{\pi}{3}rad$
(b) $csc~θ=\sqrt 2$
$\frac{1}{sin~θ}=\sqrt 2$
$sin~θ=\frac{1}{\sqrt 2}=\frac{1}{\sqrt 2}\frac{\sqrt 2}{\sqrt 2}=\frac{\sqrt 2}{2}$
$θ=45°=\frac{\pi}{4}rad$
