1
1

Delete article

Deleted articles cannot be recovered.

Draft of this article would be also deleted.

Are you sure you want to delete this article?

More than 5 years have passed since last update.

高校数学の公式

Last updated at Posted at 2018-09-18

2次関数

解の公式

2次関数を次式のように定義する。
$ax^2 + bx + c = 0 (a\neq 0)$

この時の解は次の公式で求められる。
$x = \frac{-b\pm{\sqrt{b^2 - 4ac}}}{2a}$

判別式

$D = b^2 - 4ac$としたとき、下記が成り立つ。
$D > 0$で異なる2つの解を持つ。
$D = 0$で重解を持つ。
$D < 0$で虚数解を持つ。

1
1
0

Register as a new user and use Qiita more conveniently

  1. You get articles that match your needs
  2. You can efficiently read back useful information
  3. You can use dark theme
What you can do with signing up
1
1

Delete article

Deleted articles cannot be recovered.

Draft of this article would be also deleted.

Are you sure you want to delete this article?