Note 1.1.1.
Real numbers do not include complex numbers like the square root of negative one \(\left( \sqrt{-1} \right) \text{.}\)
Section 1.1 Real Numbers
Real numbers represented as \(\mathbb{R}\) are a set of numbers that include all rational and irrational numbers. They can be positive, negative, or zero, and can be represented on the number line. The table below shows classification of real numbers with examples.
| Category | Examples |
|---|---|
| Whole numbers (\(\,\mathbb{W}\)) | \(0, 1, 2,3,4,...\) |
| Integers(\(\,\mathbb{Z}\)) | \(-4,-3,-2,0,1,2,...\) |
| Fractions | \(\frac{1}{2}, \frac{2}{3}, \frac{1}{3},\frac{5}{4},\frac{12}{6},...\) |
| Decimals | \(0.2,4.5,-2.6,-3.8,...\) |
| Irrational numbers | \(\sqrt{2},\sqrt{7}, \pi,...\) |
\({\color{blue}\text{How do we use real numbers in day-to-day activities?}}\)
We use real numbers in everyday life for tasks such as managing finances while budgeting or shopping, measuring ingredients for cooking, tracking time and distance when traveling, and interpreting data on digital devices.
