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Irrational Numbers

Master the logic of real numbers. Learn to convert fractions and decimals, identify repeating patterns, and define irrational constants like π and e. Gain practical skills in bounding square roots and ordering number sets to solve real-world estimation problems with precision.

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Verified skills you'll gain

DEVELOPING

Analyzing Number Properties

DEVELOPING

Computing with Numbers

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Course 2

Mastery of Repeating Decimals

4 lessons

17 practices

You will dive deep into the world of repeating decimals. You will learn to use professional notation to represent infinite loops, distinguish between pure and mixed repeating blocks, and use algebraic methods to convert these infinite strings back into exact rational fractions.

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Course 3

The Real Number System and Irrationality

5 lessons

16 practices

You will meet the numbers that refuse to be written as fractions. You will learn why their decimal expansions never terminate or repeat, recognize famous examples like π and e, and identify irrationals generated by square roots. Finally, you will learn to bound these numbers between integers to understand their place on the number line.

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Course 4

Estimating and Comparing Real Numbers

4 lessons

12 practices

You will turn irrational numbers into practical tools by producing rational approximations. Using trial squaring, calculator rounding, and number line plotting, you will learn to compare irrationals with rationals and estimate the results of real-world arithmetic expressions.

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From our community

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I'm impressed by the quality and can't stop recommending it. It's also a lot of fun!

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+11

I love that it's personalized. When I'm stuck, I don't have to hope my Google searches come out successful. The AI mentor Cosmo knows exactly what I need.

Faith Yim

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+14

It's an amazing product and exceeded my expectations, helping me prepare for my job interviews. Hands-on learning requires you to actually know what you are doing.

Alex Bush

Full Stack Engineer

I'm really impressed by the AI tutor Cosmo's feedback about my code. It's honestly kind of insane to me that it's so targeted and specific.

Abbey Helterbran

Tech consultant

I tried Leetcode but it was too disorganized. CodeSignal covers all the topics I'm interested in and is way more structured.

Jonathan Miller

Senior Machine Learning Engineer

+12

I'm impressed by the quality and can't stop recommending it. It's also a lot of fun!

Francisco Aguilar Meléndez

Data Scientist

+11

From our community

Hear what our customers have to say about CodeSignal Learn

I'm impressed by the quality and can't stop recommending it. It's also a lot of fun!

Francisco Aguilar Meléndez

Data Scientist

+11

I love that it's personalized. When I'm stuck, I don't have to hope my Google searches come out successful. The AI mentor Cosmo knows exactly what I need.

Faith Yim

Software Engineer

+14

It's an amazing product and exceeded my expectations, helping me prepare for my job interviews. Hands-on learning requires you to actually know what you are doing.

Alex Bush

Full Stack Engineer

I'm really impressed by the AI tutor Cosmo's feedback about my code. It's honestly kind of insane to me that it's so targeted and specific.

Abbey Helterbran

Tech consultant

I tried Leetcode but it was too disorganized. CodeSignal covers all the topics I'm interested in and is way more structured.

Jonathan Miller

Senior Machine Learning Engineer

+12

I'm impressed by the quality and can't stop recommending it. It's also a lot of fun!

Francisco Aguilar Meléndez

Data Scientist

+11