Take a protractor into the examination room, and when you encounter analytic geometry, you can immediately know what degree it is, and basically you can solve the problem immediately. If you want something else, you can use it instead.
2. The last problem in the conic curve is often too complicated to get together, so that K cannot be calculated. At this time, the special value method can be used to force the calculation of k, and the process is to combine first, then calculate δ, and use the lower David theorem to list the expression of the solution of the problem.
3. There is a step in the process of proving space geometry that I really can't think of. Just write down the conditions you don't use and draw unexpected conclusions. If the first question can't be written directly, the second question can be used directly.
4. A new method to find dihedral angle B-OA-C in solid geometry. Using cosine theorem of trihedral angle. Let dihedral angle B-OA-C be ∠OA, ∠AOB be α, ∠BOC be β and ∠AOC be γ. This theorem is: cos ∠ OA = (cos β-cos α cos γ)/sin α sin γ. Knowing this theorem, if you encounter the problem of finding dihedral angle in solid geometry in the exam, a formula will come out.
5. Mathematical (physical) linear programming problems can be solved directly without drawing.
6. The third question, the last big question in mathematics, often uses the conclusion of the first question.
7. Math (science) Choose the fill-in-the-blank graphic problem, draw it in proportion with a ruler, and the zero-based direct second.
8. If the math choice is not good, remove the maximum and minimum and choose another one.
9. The derivative multiple-choice questions of transcendental functions can be replaced by constant functions that meet the conditions, but not by linear functions.
The second kill method of multiple-choice math questions in college entrance examination is 1. If it is difficult to solve the problem from the front, we can find a qualified conclusion step by step from the choice of expenditure, or draw a conclusion from the opposite side.
2. Extreme principle: analyze the problem to be studied to an extreme state, so that the causal relationship becomes more obvious, thus achieving the purpose of solving the problem quickly. Extreme value is mainly used to find extreme value, range and analytic geometry. Many problems with complicated calculation steps and large amount of calculation can be solved instantly once extreme value analysis is adopted.
3. Exclusion method: using the known conditions and the information provided by the selection branch, three wrong answers are excluded from the four options, so as to achieve the purpose of correct selection. This is a common method, especially when the answer is a fixed value or has a numerical range, special points can be used instead of verification to exclude it.
4. Number-shape combination method: a method of making a figure or image that conforms to the meaning of the question according to the conditions of the question, and obtaining the answer through simple reasoning or calculation with the help of the intuition of the figure or image. The advantage of the combination of numbers and shapes is intuitive, and you can even measure the result directly with a square.
5. Recursive induction: a method of reasoning through topic conditions, looking for rules, and thus summing up the correct answer.
6. Valuation selection method: For some problems, due to the limitation of subject conditions, it is impossible (or unnecessary) to make accurate calculations and judgments. At this time, we can only get the correct judgment method from the surface by means of estimation, observation, analysis, comparison and calculation.