论文部分内容阅读
二次函数解析式中的参数,呼风唤雨、鬼使神差般地左右着抛物线的活动轨迹.演绎出一道道倍受青睐的好题.本文着重以抛物线的变化为线索,求解二次函数解析式中的参数.望同学们借鉴.一、参数使两个变量构成二次函数例1若y=(k2+2k)xk2+k-3kx+1是关于自变量x的二次函数,则k的值为().(A)1(B)-2(C)1或2(D)不存在分析本例是由函数关系求参数,准确理解二次函数一般式:y=ax2+bx+c(a,b,c是常数,且a≠0)的意义是解题的关键.解∵y=(k2+2k)xk2+k-3kx+1是
The parameters of the quadratic function analytic formula, do anything they want, make the most of a ghost makes the parabolic activity trajectory. Deduce a good way to favor .This paper focuses on the change of the parabola as a clue, solves the quadratic function analytic parameters I hope the students learn from I. First, the parameters of the two variables constitute a quadratic function Example 1 If y = (k2 +2 k) xk2 + k-3kx + 1 is a quadratic function on the argument x, the value of k is ( (A) 1 (B) -2 (C) 1 or 2 (D) does not exist Analysis This case is to find the parameters by the functional relationship, accurate understanding of the quadratic function general formula: y = ax2 + bx + c b, c is a constant, and a ≠ 0) is the key to solution. Solution ∵y = (k2 + 2k) xk2 + k-3kx + 1 is