The difficulty of the three small questions in this question is gradually increasing. It is the finale to examine students' ability to grasp the monotonicity of functions in depth, which requires higher thinking. The answer is that it is very important for gz.qiujieda.com/exercise/math/804062/ to guide the reasonable deformation of the resolution function from the perspective of solving process, because it directly affects the judgment of derivative symbols and is an important breakthrough to solve this problem.