高二“希望杯”全国数学邀请赛
如图1、一个正方体的容器ABCD-中盛满了油后,在相邻两侧面的中心处出现了两个小孔,若恰当地将容器放置。可使流出的油量达到最小,这个最小值是正方体容器容量的。
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Ahyperbola(双曲线)wjthvertices(顶点)(-2,5)and(-2,-3),has an asynptote(渐近线)that passes the point(2.5) Then an equarionk of the hyperbola is
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Suppose the least distance fron poinrs of the xurve(曲线)to the y-axis is then the velue of a is
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Let a and be the length of two sides of a rectangle (矩形),rotate(旋转)the rectangle about its
diagonal(对角线),then the volume(体积) of the revolution(旋转休) obtained is equal to________。
Given BC=1,in a triangle(三角形)ABC, then the range of length of the side AB (or AC) is_____________________。