Introduction – Surds

Topic Content:

Rational Numbers:

Some numbers can be expressed as ratios of two integers, e.g. \( \frac {a}{b} \)where a and b are integers and b≠0, such numbers are called rational numbers.

Examples of rational numbers: \( \scriptsize 3, \; \normalsize \frac {2}{5}, \; \scriptsize 2.7 \; e.t.c \)

All integers are rational numbers since each integer n can be written in the form \( \frac{n}{1} \). For example \( \frac{5}{1} \)

A repeating decimal is always a rational number. Repeating decimals are those in which one number or a pattern of numbers repeats indefinitely. For example, the numbers 0.2222, 0.66666, 0.17171717, 1.333… and 8.1414… are repeating decimals.

Irrational Numbers:

Other numbers cannot be expressed as ratios of integers.