Knowunity AI

Open the App

Subjects

数学数学21 views·Updated May 21, 2026·1 page

関数のグラフと増減の基礎

関数の増減とグラフの関係を理解することで、数学の問題がもっと簡単に解けるようになる。グラフを見れば関数の増減が分かるし、逆に関数の増減が分かればグラフの形も予想できるんだ。

1
of 1
# 関数の増減とグラフ

1. Overview

*   関数の増減とグラフの関係について理解する。
*   グラフから関数の増減を読み取れるようにする。
*   関数の増減からグラフの概形を把握できるようにする。

2. Key definitions and concept

関数の増減とグラフ

関数の増減って聞くと難しそうだけど、実はグラフを見れば一目瞭然なんだ。右上がりなら増加、右下がりなら減少って覚えておこう。

単調増加は、xが大きくなるとyも大きくなる状態で、グラフは右上がりになる。単調減少は逆で、xが大きくなるとyは小さくなり、グラフは右下がりだ。グラフが水平なら関数は一定値を保っている。

関数 f(x)=x36x2+9xf(x) = x^3 - 6x^2 + 9x の例では、まず微分して f(x)=3x212x+9f'(x) = 3x^2 - 12x + 9 を求める。f(x)=0f'(x) = 0 となるxを見つけると、x = 1, 3が出てくる。これらの点で関数の増減が切り替わるんだ。

増減表を作って整理すると、x < 1で増加、1 < x < 3で減少、x > 3で再び増加することが分かる。この情報があれば、グラフの大まかな形が描けるようになる。

💡 ポイント: 増減表は関数のグラフを描くための設計図みたいなもの。一度作れば、グラフの全体像が見えてくる!

We thought you’d never ask...

What is the Knowunity AI companion?

Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.

Where can I download the Knowunity app?

You can download the app from Google Play Store and Apple App Store.

Is Knowunity really free of charge?

That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.

Most popular content in 数学

9

Most popular content

9

Can't find what you're looking for? Explore other subjects.

Students love us — and so will you.

4.6/5App Store
4.7/5Google Play

The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.

Stefan SiOS user

This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.

Samantha KlichAndroid user

Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.

AnnaiOS user

数学数学21 views·Updated May 21, 2026·1 page

関数のグラフと増減の基礎

関数の増減とグラフの関係を理解することで、数学の問題がもっと簡単に解けるようになる。グラフを見れば関数の増減が分かるし、逆に関数の増減が分かればグラフの形も予想できるんだ。

1
of 1
# 関数の増減とグラフ

1. Overview

*   関数の増減とグラフの関係について理解する。
*   グラフから関数の増減を読み取れるようにする。
*   関数の増減からグラフの概形を把握できるようにする。

2. Key definitions and concept

Sign up to see the content. It's free!

  • Access to all documents
  • Improve your grades
  • Join milions of students

関数の増減とグラフ

関数の増減って聞くと難しそうだけど、実はグラフを見れば一目瞭然なんだ。右上がりなら増加、右下がりなら減少って覚えておこう。

単調増加は、xが大きくなるとyも大きくなる状態で、グラフは右上がりになる。単調減少は逆で、xが大きくなるとyは小さくなり、グラフは右下がりだ。グラフが水平なら関数は一定値を保っている。

関数 f(x)=x36x2+9xf(x) = x^3 - 6x^2 + 9x の例では、まず微分して f(x)=3x212x+9f'(x) = 3x^2 - 12x + 9 を求める。f(x)=0f'(x) = 0 となるxを見つけると、x = 1, 3が出てくる。これらの点で関数の増減が切り替わるんだ。

増減表を作って整理すると、x < 1で増加、1 < x < 3で減少、x > 3で再び増加することが分かる。この情報があれば、グラフの大まかな形が描けるようになる。

💡 ポイント: 増減表は関数のグラフを描くための設計図みたいなもの。一度作れば、グラフの全体像が見えてくる!

We thought you’d never ask...

What is the Knowunity AI companion?

Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.

Where can I download the Knowunity app?

You can download the app from Google Play Store and Apple App Store.

Is Knowunity really free of charge?

That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.

Most popular content in 数学

9

Most popular content

9

Can't find what you're looking for? Explore other subjects.

Students love us — and so will you.

4.6/5App Store
4.7/5Google Play

The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.

Stefan SiOS user

This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.

Samantha KlichAndroid user

Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.

AnnaiOS user