First, advanced mathematics.
The high number and big questions 15 and 19 examine the limit problem, one is the function limit problem, which is less difficult; One is the limit problem of sequence. Monotone bounded sequence must have a limit, which is difficult. It is difficult to estimate the position of students in the proof of monotonicity boundedness. 16 is a double integral, which is relatively basic, but the calculation amount is not small, which wastes time for candidates with poor calculation ability.
The problem 17 is a conditional extreme value problem, and the objective function needs to be found by itself, which is satisfactory, but it is also troublesome to calculate. The problem 18 is a power series expansion problem. It is estimated that many students have forgotten the power series expansion method of finding the whole integral first and then finding the derivative item by item.
The small question mainly examines the definition of derivative, the sign of limit, the mean value theorem of integral, the comparability of definite integral, the tangent equation of derivative, indefinite integral, differential equation, difference equation and the economic application of derivative.
Second, linear algebra.
The definition of quadratic form is investigated in 20 questions of linear algebra, which is transformed into a problem of linear equations. The second problem is that it is easier to convert the general form into the standard form by collocation, and then convert the standard form into the standard form. Students may be familiar with the standard form, but not with it. 2 1 The necessary and sufficient conditions of matrix equivalence and the solution of matrix equation are investigated. The second question is similar to the real question of 20 14, but it should be noted that p is the value of reversible matrix K.
Third, probability statistics.
The big problems of probability theory and mathematical statistics tend to be flexible in recent three years. Question 22 examines the definition of covariance, the distribution of two discrete random variable functions, and pays attention to how to transform unknown random variables into known random variables. Question 23 is also an absolute value question, which is a popular test center in recent two years. Maximum likelihood estimation also needs everyone's understanding memory, not mechanical training.
The relationship between probability density and distribution function, the distribution of unified measure in normal population and the essence of probability are investigated in small questions.