Rational number definition:-
In Algebra 1, A number which can be expressed in the form of p/q where p and q are integers and q ? 0 is called rational number. Since the q may be equal to 1 therefore all integers are rational numbers. The set of all rational numbers are denoted by Q. For example 4 is a rational number because we can write 4 as 4/1 and 1?0. Similarly the numbers 1/2, -5/2 etc are also rational number.
Any repeating or terminating decimal numbers are also rational numbers.
Adding Rational Numbers
When we add two rational numbers , we will get a rational number , The following Adding Rational Numbers example from Algebra 1 problems will explain in in detail.
$\frac{a}{b}$ + $\frac{c}{d}$ = $\frac{ad + bc}{bd} $ is also rational.
Multiplying Rational Numbers
Rational numbers are closed under addition, subtraction, multiplication and division also.
Thus for rational number a/b and c/d; a, b, c, d ? 0.Here is few examples from Algebra 1 answers.
I) $\frac{a}{b}$ - $\frac{c}{d}$ = $\frac{ad - bc}{bd}$ is also rational.
II) $\frac{a}{b}$ x $\frac{c}{d}$ = $\frac{ac}{ bd}$ is also rational.
III) $\frac{a}{b}$ รท $\frac{c}{d}$ = $\frac{ad}{ bc}$ is also rational.
Rational and Irrational Numbers
Numbers which are not rational but which can be represented by points on the number line are called irrational numbers. Example for irrational numbers are ?6, ?2, pi , e etc. The decimal representation of irrational number continues forever without repeating.