📐数学•Medium•1234 已解答
Solve Quadratic Equations
Learn how to solve quadratic equations using different methods including factoring, completing the square, and the quadratic formula.
题目
Solve the quadratic equation: x² + 5x + 6 = 0
分步解答
1
识别二次方程的标准形式
标准形式为 ax² + bx + c = 0,其中:
- a = 1
- b = 5
- c = 6
2
使用因式分解法
寻找两个数字 p 和 q,使得:
- p + q = b = 5
- p × q = c = 6
这两个数字是 2 和 3
3
写出因式分解形式
x² + 5x + 6 = (x + 2)(x + 3) = 0
4
求解 x 的值
根据零因子定理:
- x + 2 = 0 或 x + 3 = 0
- x = -2 或 x = -3
因此,解为 x = -2 或 x = -3