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在二次函数的学习中,有些同学由于概念不清、考虑不周,解题时常会出现一些错误.现将常见错误归类剖析如下,希望你能从中汲取教训,不再犯类似的错误.一、没有理解二次函数的概念而错解例1下列函数关系式:y=(x-2)2+2,y=(x-1)(x+3),y=x2+1,y=(3x+2)(4x-3)-12x2,y=xax2+bx+c,其中y一定是x的二次函数的有().A.2个B.3个C.4个D.5个错解:认为只有y=(x-1)(x+3)不是二次函数,选C;认为都是二次函数,选D.正解:只有y=(x-2)2+2和y=(x-1)(x+3)一定是二次函
In the quadratic function of learning, some students because of the concept of unclear, ill-considered, often a number of mistakes in the problem-solving. Common mistakes are now classified as follows, I hope you can learn from it, no longer make a similar mistake. , Without understanding the concept of quadratic function, the following functional relation of Example 1 is wrongly interpreted: y = (x-2) 2 + 2, y = x- 1 x + 3, y = x2 + 1, y = (3x + 2) (4x-3) -12x2, y = xax2 + bx + c, where y must be a quadratic function of x () .A.2 B.3 C.4 D.5 A wrong solution: that only y = (x-1) (x +3) is not a quadratic function, choose C; that are quadratic function, the election D. Positive Solutions: Only y = (x-2) 2 +2 and y = (x-1) (x + 3) must be a quadratic letter