Sets of Numbers There are different sets of numbers. In this lesson you will learn what these sets are. This diagram shows how all the sets of numbers relate to each other.
All the possible numbers that exist form the set of Real Numbers. The short way of writing these numbers is R. The Real Numbers can be divided into two different types which are Rational Numbers and Irrational Numbers. Irrational Numbers are numbers that have non-repeating and non-ending (non-terminating) decimals. For example the square root of 2. Try finding the square root of 2 on your calculator. What do you get? You should get something that looks like this 1.14213562. Note that the decimal numbers do not repeat each other and if a person was to continue these numbers would continue forever (which is known as infinity) When these circumstances exist then the number is an irrational number. To see the difference look at the fraction 1/3. This means 1divided by 3. If you do this on your calculator you would get an answer of 0.333333333333 (the 3 would continue for infinity). Because the 3 repeats 1/3 is not an irrational number. In fact, this is what we call a Rational Number.
See if you can sort out Irrational and Rational Numbers. Use your calculator to check to see if you identified them correctly. 1. 2/5 2. square root of 5 3. 2/3 4. 1.3456 5. square root of 100 |
