Look at Fig. 2.34. Mark a point


(a) A which is in the interior of both 1 and 2.


(b) B which is in the interior of only 1.


(c) Point C in the interior of 1.


Now, state whether points B and C lie in the interior of 2 also.


Yes, points 6 and C lie in the interior of 2 also. Since, 1 is in interior of 2, then all the points lying inside the 1, will also lie inside the 2.


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