Judging the monotonicity of derivative function in senior high school mathematics: the derivative function deviates from the original function as G (x) = 2x 2-2ax+ 1. Why do you want to open it from A < =0 or a>0? ... What do you mean, how did you come up with the idea of classified discussion? Whether to discuss it depends on the meaning of the question. The monotonicity of derivative function in high school mathematics is judged according to the positive and negative of derivative function.

For example, in this problem, the derivative function G (x) = 2x 2-2ax+ 1 is a quadratic function with an upward opening, so we can discuss its pros and cons with images. Because A is an uncertain number, when the discriminant is less than 0, A 2: = 2, and g(x) is positive or negative. Therefore, the solution when g(x)=0 is required, and the increase or decrease range can be judged by the image, but the premise should be paid attention to: the amplitude of A. 。

I wonder if you are satisfied with this answer?