rectangle/?' e 2ft which contains T. If A and B lie on side EF, we can reach the conclusion in a similar way. Case 2: A, 5 lie on two opposite sides ofR. First we translate T in R such that A or B lies on one of the corners of /?. We may assume without loss of generality that B lies on the corner F and A lies on EH, as shown in Figure 3(b). Recall that R is not the circumscribed rectangle of T, so C does not lie on GH . If C lies on FG, then A lies in the interior of R by reasoning as in case 1, contradicting our assumption here. So C lies in the interior of R. Notice that ZFAH > 90°, then we can rotate T around vertex B clockwise slightly such that both A and C lie in the interior of/?, and therefore we obtain a smaller rectangle/? e $1 that contains T. Case 3:A,B lie on two adjacent sides of/?. We may assume that A lies in the relative interior of EF and in the relative interior of FG, as shown in Figure 3(c). It is clear that C lies in the region formed by pentagon EABGH. Since /? is not a circumscribed rectangle of T, C lies either in the interior of /?, or on the relative interior of EH or GH. Thus we conclude that there exists a smaller rectangle K g 2ft which contains T.
rectangle/?' e 2ft which contains T. If A and B lie on side EF, we can reach the conclusion in a similar way. Case 2: A, 5 lie on two opposite sides ofR. First we translate T in R such that A or B lies on one of the corners of /?. We may assume without loss of generality that B lies on the corner F and A lies on EH, as shown in Figure 3(b). Recall that R is not the circumscribed rectangle of T, so C does not lie on GH . If C lies on FG, then A lies in the interior of R by reasoning as in case 1, contradicting our assumption here. So C lies in the interior of R. Notice that ZFAH > 90°, then we can rotate T around vertex B clockwise slightly such that both A and C lie in the interior of/?, and therefore we obtain a smaller rectangle/? e $1 that contains T. Case 3:A,B lie on two adjacent sides of/?. We may assume that A lies in the relative interior of EF and in the relative interior of FG, as shown in Figure 3(c). It is clear that C lies in the region formed by pentagon EABGH. Since /? is not a circumscribed rectangle of T, C lies either in the interior of /?, or on the relative interior of EH or GH. Thus we conclude that there exists a smaller rectangle K g 2ft which contains T.
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