我们知道,对于式子ab,当a=0时,不论b为任何实数,ab的值都是0.这可以称之为零因式的性质.本文拟利用零因式的性质解答一类图像必过定点的问题.例1(2011年桂林中考)直线y=kx-1一定经过点().(A)(1,0)(B)(1,k)(C)(0,k)(D)(0,-1)解令x=0,则不论k为任何实数,kx都是0.当x=0时,y=k·0-1=-1.∴直线y=kx-1一定经过点(0,-1).故选(D).例2无论m为任何实数,二次函数y=x2+(2-m)x+m的图像总过的点是 We know that for the expression ab, when a = 0, regardless of whether b is any real number, the value of ab is 0. This can be called the nature of the zero factor. This paper proposes to use the nature of zero factor to solve a class of images. The problem must be fixed. Example 1 (Guilin test in 2011) Line y=kx-1 must pass ().(A)(1,0)(B)(1,k)(C)(0,k) (D) (0, -1) Let x=0 be zero, then k is zero regardless of whether k is any real number. When x=0, y=k·0-1=-1. ∴Linear y=kx- 1 must go through the point (0,-1). So we pick (D). Example 2 The point where the image of the quadratic function y=x2+(2-m)x+m always passes, regardless of whether m is any real number