Quadratic Equations and Factorisation | 二次方程与因式分解

📚 Quadratic Equations and Factorisation | 二次方程与因式分解

This revision guide focuses on one of the most tested areas in Edexcel IGCSE Mathematics: quadratic expressions and equations. You will learn how to factorise monic and non-monic quadratics, solve equations using factorisation, apply the quadratic formula, complete the square, and use the discriminant. Every method is presented in the exact style needed for the Edexcel IGCSE examination.

本复习指南聚焦 Edexcel IGCSE 数学中出题率最高的内容之一：二次表达式与二次方程。你将学习如何分解首项系数为 1 和不为 1 的二次式，用因式分解法解方程，使用求根公式，掌握配方法以及运用判别式。每一种方法都以 Edexcel IGCSE 考试所要求的标准形式呈现。

1. What Is a Quadratic Equation? | 什么是二次方程？

In Edexcel IGCSE Mathematics, a quadratic equation is a polynomial equation of degree 2. It can be written in the general form shown below, where a, b and c are real constants and a ≠ 0.

在 Edexcel IGCSE 数学中，二次方程是次数为 2 的多项式方程。它可以写成以下一般形式，其中 a、b、c 是实数常数，且 a ≠ 0。

ax² + bx + c = 0

The highest power of the unknown variable x is 2. If a = 0, the equation becomes linear, not quadratic. The graph of y = ax² + bx + c is a parabola, and the roots of the equation are the x-coordinates where this parabola crosses the x-axis.

未知数 x 的最高次数是 2。如果 a = 0，方程就变成一次方程，而不是二次方程。函数 y = ax² + bx + c 的图像是抛物线，方程的根就是这条抛物线与 x 轴交点的横坐标

Published by TutorHao | IGCSE Mathematics Revision Series | aleveler.com

更多咨询请联系16621398022（同微信）