$..., -3, -2, -1, 0, 1, 2, 3, 4, ...$
Integers divisible by $1$ and itself only. Smallest prime is $2$.
$\frac{\text{integer}}{\text{integer}}$ — e.g., $\frac{4}{7}, -3\frac{1}{8}, 0.3, 2.\dot{6}\dot{5}, 92, \sqrt{16}$
Cannot be expressed as fractions — e.g., $\pi, \sqrt{2}, e$
All rational and irrational numbers combined.
where $n$ is an integer, and $1 \leq A < 10$
| Prefix | Symbol | Value |
|---|---|---|
| tera | T | $10^{12}$ |
| giga | G | $10^{9}$ |
| mega | M | $10^{6}$ |
| kilo | k | $10^{3}$ |
| — base unit — | ||
| milli | m | $10^{-3}$ |
| micro | μ | $10^{-6}$ |
| nano | n | $10^{-9}$ |
| pico | p | $10^{-12}$ |