极坐标是高中数学选修内容,但它是高考必考内容,同学们对极坐标的应用主要停留在圆的参数方程与普通方程的转化上。事实上,由于极坐标中点的坐标表示的是到极点的距离和旋转的角度。因此,在圆锥曲线中,绕原点互相垂直的动弦问题,用极坐标处理往往更简便。下面举例说明。例1(2014年北京卷)已知椭圆 Polar coordinates is a high school mathematics elective content, but it is the college entrance examination will be content, students use polar coordinates mainly stay in the circle of the parametric equation and the conversion of ordinary equations. In fact, since the coordinates of the mid-point of the polar coordinates indicate the distance to the extreme point and the angle of rotation. Therefore, in conic curves, the problem of moving strings that are perpendicular to each other at the origin point is often easier to deal with. Here’s an example. Example 1 (2014 Beijing volume) Known ellipses