有关应用题中最值问题,在实际条件的约束下,不能仅靠使用重要不等式求出最值,需要借助比较法,把问题转化为与端点值的大小关系问题.例1某种印刷品,单面印刷,其版面(如图中阴影部分)排成矩形,版面面积为A,它的左右两边都要留宽为a的空白,上下两边都要留有宽为b的空白,且印刷品左 Regarding the problem of the value of the application problem, under the constraint of the actual conditions, it is not possible to rely only on the use of important inequalities to find the best value, but rather to use the comparison method to convert the problem into a relationship with the value of the end point value. Example 1 A kind of printed matter, single Face printing, its layout (shaded in the figure) is arranged in a rectangle, the layout area is A, its left and right sides must be left blank for the a blank, both sides have to leave a width of b, and the left of the print