(i) Let . Then,

Clearly, is the set of all points lying on or above the line in -plane, is the set of all points lying on the circle having centre at and radius 3 and is the set of all points on the line .
The line intersects the circle at and out of which lies in the region represented by .
contains exactly one point.

(ii) Clearly, is the only point in satisfying . We observe that and both lie on the circle , and their mid-point is the centre of the circle. So, and are the end-points of a diameter of the circle .

(iii) Clearly, represents and is any point inside the circle .

Clearly,

Now,

Hence, lies between -3 and 9.

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