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在学习直线方程时,我们经常会碰到下面两个题目:题1如图1,直线l过P(3,2)与x,y轴正半轴交于A,B两点,O为坐标原点,求△OAB面积的最小值,并求此时的直线方程.题2如图2,直线l过P(3,2)与射线y=4x(x>0)及x轴正半轴交于A,B,O为坐标原点,求△OAB面积的最小值.对于题1,同学们通常会用截距式.设直线l与x,y轴正半轴交于A(a,0),B(0,
When learning the linear equation, we often encounter the following two topics: Question 1 As shown in Figure 1, the line l over P (3,2) and x, y axis is a half-way intersection at A, B two points, O coordinates Origin, find the minimum value of △ OAB area, and find the linear equation at this time .Table 2 As shown in Figure 2, the line l through P (3,2) and ray y = 4x (x> 0) For A, B, O is the origin of the coordinates, find the minimum value of △ OAB area.For the title 1, the students usually use intercept type.It is assumed that the straight line l and the x, , B (0,