点到直线距离公式在教材上、资料上有很多种证法,本篇将结合高二学生的实际,根据学生已掌握的知识,介绍两种新证法.图1已知直线l的方程:Ax+B y+C=0(A、B不全为0),P(x0,y0)为平面上任一点,求点P到直线l的距离.证法1(向量方法)如图1,设P1(x1,y1)为直线l上一点,G为过点P(x0,y0)作 The point-to-straight distance formula has many kinds of proofs on the textbooks and materials. This article will combine the actual conditions of Grade Two students and introduce two new proofs based on the students’ knowledge. Figure 1 Equation of the known straight line l: Ax +B y+C=0 (A and B are not all 0), P(x0, y0) is any point on the plane, and the distance from point P to the straight line l is shown. The proof method 1 (vector method) is shown in Fig. 1, and P1 is set ( X1,y1) is a point on the line l, G is the point P(x0,y0)