Mathematics is a subject for that person, especially for those smart students who tend to think too much. Let me sort out the summary of the important and difficult knowledge of mathematics in grade three for your reference only.

Analytic functions (linear function, inverse proportional function, quadratic function) of senior high school entrance examination knowledge account for about 15% of the total score.

Quadratic function, in particular, is the key and difficult point of the senior high school entrance examination. It will appear in filling in the blanks, selecting topics and solving problems, with many knowledge points and changeable questions.

Moreover, the last two questions in the test paper usually have a solution, and the general quadratic function and the images and properties of quadratic function, as well as the triangle and quadrilateral synthesis questions are difficult to apply. There is a certain difficulty.

If you don't master this link well, it will directly affect the algebra foundation and have a great influence on the results of the senior high school entrance examination.

The application questions in the senior high school entrance examination account for about 30% of the total score.

Including equation (group) application, linear inequality (group) application, function application, triangle solution application and probability statistics application.

Generally, there will be two or three answers (about 30 points) and two or three multiple-choice questions and fill-in-the-blank questions (10-15 points), accounting for about 30% of the total score of the senior high school entrance examination.

Geometric problem formula theorem 1, ① line l intersects with ⊙O D⊙R2 line l is tangent to ⊙O D = R3 line l separates from ⊙O D ⊙ R.

2. The judgment theorem of tangent is that the outer end of the radius and the straight line perpendicular to this radius are the tangents of the circle.

3. The property theorem of tangent The tangent of a circle is perpendicular to the radius passing through the tangent point.

4. It is inferred that the straight line passing through the center of the circle and perpendicular to the tangent must pass through the tangent point.

5. Inference 2 A straight line passing through the tangent point and perpendicular to the tangent line must pass through the center of the circle.

6. The tangent length theorem leads to two tangents of a circle from a point outside the circle, and their tangent lengths are equal. The line between the center of the circle and this point bisects the included angle of the two tangents.

7. The sum of two opposite sides of a circle's circumscribed quadrilateral is equal.

8. Chord tangent angle theorem The chord tangent angle is equal to the circumferential angle of the arc pair it clamps.

9. From this, it can be inferred that if the arc sandwiched between two chordal angles is equal, then the two chordal angles are also equal.

10, intersection chord theorem The length of two intersecting chords in a circle divided by the product of the intersection point is equal.

The above is the summary of the important and difficult knowledge of mathematics in grade three that I have compiled for you.