(i)
(ii)
SOLUTION:
(i) According to the given question,
\[\angle AOB\text{ }=\text{ }2\angle AOB\text{ }=\text{ }2\text{ }x\text{ }{{50}^{o}}~=\text{ }{{100}^{o}}\]
[Angle at the center is double the angle at the circumference subtend by the same chord]
Also, \[OA\text{ }=\text{ }OB\]
\[\angle OBA\text{ }=\angle OAB\text{ }=\text{ }c\]
\[c\text{ }=\text{ }({{180}^{o}}-\text{ }{{100}^{o}})/\text{ }2\text{ }=\text{ }{{40}^{o}}\]
(ii) According to the given question,
We have, \[\angle APB\text{ }=\text{ }{{90}^{o}}~\][Angle in a semicircle]
\[\angle BAP\text{ }=\text{ }{{90}^{o}}-\text{ }{{45}^{o}}~=\text{ }{{45}^{o}}\]
Now, \[d\text{ }=\angle BCP\text{ }=\angle BAP\text{ }=\text{ }{{45}^{o}}\]
[Angles subtended by the same chord on the circle are equal]