What's a Real Number?

What's a Real Number?

Note:

Real numbers are numbers that can be found on the number line. This includes both the rational and irrational numbers. This tutorial explains real numbers and gives some great examples. Take a look!

Keywords:

  • definition
  • real number
  • rational
  • irrational
  • number lines

Background Tutorials

  • Find and position integers and other rational numbers on a horizontal or vertical number line diagram; find and position pairs of integers and other rational numbers on a coordinate plane.

  • Understand that multiplication is extended from fractions to rational numbers by requiring that operations continue to satisfy the properties of operations, particularly the distributive property, leading to products such as (-1)(-1) = 1 and the rules for multiplying signed numbers. Interpret products of rational numbers by describing real-world contexts.

      • What's a Rational Number?What's a Rational Number?

      What's a Rational Number?

      There are lots of different kind of numbers that you should know about, and that includes rational numbers. Check out the tutorial!

  • Use rational approximations of irrational numbers to compare the size of irrational numbers, locate them approximately on a number line diagram, and estimate the value of expressions (e.g., π^2).

      • How Do You Estimate the Square Root of a Non-Perfect Square?How Do You Estimate the Square Root of a Non-Perfect Square?

      How Do You Estimate the Square Root of a Non-Perfect Square?

      Trying to take the square root of a number that is not a perfect square? Think you need a calculator? Think again! This tutorial will show you how to estimate the square root of a number that is not a perfect square without the use of a calculator!

  • Use square root and cube root symbols to represent solutions to equations of the form x^2 = p and x^3 = p, where p is a positive rational number. Evaluate square roots of small perfect squares and cube roots of small perfect cubes. Know that √2 is irrational.

      • What's a Perfect Square?What's a Perfect Square?

      What's a Perfect Square?

      Anytime you square an integer, the result is a perfect square! The numbers 4, 9, 16, and 25 are just a few perfect squares, but there are infinitely more! Check out this tutorial, and then see if you can find some more perfect squares!