基本想法:若几个元素在问题中所处的地位完全等同,不妨称之为等价元素,因为地位完全一致,所以这些元素所满足的等式也是完全相同的,即多个不同的元素满足同一等式,于是这些元素所代表的量可以看作是同一方程的解,从而可以利用该方程的性质解决问题.下面以具体的几个问题的解决来说明这一想法,供高中师生教与学时参考.题目1如图1,P是抛物线y2=2x上的动点,点B,C在y轴上,圆(x-1)2+y2=1内切于△PBC,求△PBC的面积 The basic idea: If the position of several elements in the question exactly the same, may wish to call the equivalent elements, because the status is exactly the same, so these elements satisfy the equation is exactly the same, that is, a number of different elements to meet The same equation, so the amount represented by these elements can be seen as the solution of the same equation, which can be used to solve the problem of the nature of the equation below to solve the specific problem to illustrate this idea for senior high school teachers and students to teach 1, P is the moving point on the parabola y2 = 2x, point B, C is on the y-axis, the circle (x-1) 2 + y2 = 1 is inscribed on the △ PBC, Area