In fact, this question is normal. You still have more than a year to do some big function problems, contact more and summarize more. In fact, the routines of big function questions are almost the same. Discuss by classification with the proof results of the previous question, and sort out arbitrariness and existence by scaling and mathematical induction. As long as you keep your thinking clear, carefully calculate the transformation (the probability of error in this function is very small). However, it is necessary to explain that some function problems are really difficult to come up with in strange ways. Just do such a problem according to your own interests. It is difficult to appear in the examination room (under normal circumstances) and it is estimated that it is difficult to do it. You should learn to give up according to your own ability. Senior three graduation party floats by. . . . . .