Try 6, choose 6 and fill in the blanks. The second exam does not necessarily have the topic of number theory, but some applications of elementary number theory. In fact, it depends on the understanding and imagination of the theorem. The second test can only confirm that there is a plane geometry problem. Number theory has nothing to do with high school mathematics. It's no problem to learn at any time. Then you try number theory, there will be some involved, at least some theorems will be known, and then you do some problems. Look at the steps and grade three questions. If you buy a tutorial, you can study systematically. The examination time is about 10 months, so you can take it once in Grade Two and once in Grade Three.

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