Without loss of generality, we may put point B at the corner F and A on segment EH, as shown in Figure 5. Let ZEFA = a, then a e [f^, f ] since EF < ¡EG]. Then we have u = cosa and v = cu = cos(f - a), and hence Vl - u2 = (2c - V3) m which implies u = ; 1 - . Therefore, 2Jc2 - v3c + 1 v = cu = i ç _ - . Thus we can conclude that the rectangle with sides M _ ļ - an^ v _ _ - ç^ - js the smallest rectangular ° cover of 2Vc2 - ßc + 1 2>/c2 - N^c + 1 equilateral triangle ABC with side 1 among all the rectangles similar to Ķ, and also covers S, by Lemma 1. This proves (b). The proof is complete.