She Becomes Ugly if She Doesn’t Study

In the usual math exams, even if the papers are difficult, she has never been so tight.

Tang Su looked at question 21, which was an answer question that examined the combination of sequence and probability. This question scored 12 points. The title is very long, almost 200 words, and there is a diagram. After reading the question, Tang Su began to think about the direction of the investigation. In the past, whether it was a number sequence short answer question or a question related to probability and statistics, it generally appeared in the 18th or 19th question, and the difficulty of the questions was average or medium. And in 21 questions, the difficulty of the inspection is greatly increased.

Tang Su thought about it for about 3 minutes, and after he had an idea, he started to write.

The first question asks for the distribution column.

For this question, Tang Su first obtained the distribution function, and then obtained the distribution column from the distribution function.

Then Tang Su asked the second question. The second question asked to verify the proportional sequence and write the general term formula.

Tang Su touched her head. The problem was really difficult. She had never done such a difficult number sequence problem before.

And this question is not a lot of calculations, but it is a little different from the thinking angle of the questions they usually do, it is very novel, and it is also a bit tricky.

Tang Su didn't care, because she didn't have much time to think, she started to write directly. The proof question was very focused on steps, so she wrote each step clearly. As for the final score, it depends on the grading.

It took 12 minutes for Tang Su to finish 21 questions.

There are still 20 minutes left until the end of the exam.

Tang Su immediately looked at the 22nd question, the last one to answer the question, this question is very short, only two lines, the first question and the second question are proofs. Tang Su remembered the chapter on inequality that she learned in the second semester of high school, and she didn't find it difficult when she learned this chapter.

In normal exams, inequality proof questions are rarely used as the finale questions, and sometimes the knowledge of this test center will not appear in the answering section, so Tang Su is really inexplicable that this test center has the finale question.

After looking at it for a minute, Tang Su felt that she had no idea, and she immediately turned over the test paper.

She didn't forget that she still had 16 fill-in-the-blank questions and 12 multiple-choice questions that she had yet to do.

And these two questions cannot be more difficult than the final question.

So Tang Su decided to solve these two questions first, and had time to do the final final question.

Tang Su did the 16th question first. This time she drew directly on the scratch paper. She drew half the court and then another triangle. After the drawing, she determined that the knowledge point to be examined is to solve the problem of the combination of triangles and trigonometric functions.

A lot of formulas appeared in Tang Su's mind, and in an instant, she had an idea, so after a simple calculation, she figured out the answer.

After completing the 16 questions, Tang Su saw that there were still 16 minutes before the end of the exam.

Tang Su did 12 more questions.

She had an idea for 12 questions before, and she also figured out the answer, but the answer was not in the options, so her thinking should be wrong.

So Tang Su changed the method. Instead of directly calculating the answer, she tried to substitute the exclusion method. In the end, she excluded A and B. Between C and D, Tang Su used a problem that she seldom used. Method, estimation method, through this method, Tang Su estimated the value to be three times the square root of 3, so Tang Su changed the original D to C.

As for whether it is right or not, she doesn't care, because there is no time for it.

There are 13 minutes left until the exam.

Tang Su spent a minute checking the answers to the multiple-choice questions. After confirming that there were no wrong answers, she turned to the last page of the test paper and started to do question 22.