Key knowledge of mathematics in the first half of grade three:
Chapter 21 Quadratic Radicals
Emphasis: Concepts, properties and operations related to quadratic roots.
Difficulty: the denominator of the operation of quadratic square root is physical and chemical, and the size is relatively large.
Error-prone point: the operation of quadratic root, symbol
Chapter 22 One-variable quadratic equation
Emphasis: Definition, solution, Vieta's theorem and application of quadratic equation in one variable.
Difficulties: solution (matching method) and its application, Vieta theorem.
Error-prone point: the solution of quadratic equation in one variable
Chapter 23 Rotation
Emphasis: central symmetry (definition, properties, drawing and application)
Difficulty: application of rotation (typical topic)
Error-prone point: the difference between central symmetry and central symmetry graphics
Chapter 24 Circle
Emphasis: vertical diameter theorem, position relationship with circle, sector area, arc length formula, tangent length theorem.
Difficulty: circular power theorem
Error-prone point: the side development diagram of the cone
The compulsory test in the senior high school entrance examination: the proof of the tangent of the circle
Chapter 25 Preliminary Probability
Key points: solutions of events and probabilities (list method and tree diagram)
Difficulty: the solution of probability when an experiment involves multiple factors.
Error-prone points: repetition and omission