The real number system is a collection of all the numbers that can be represented on a real line. This system includes all rational and irrational numbers. Every possible number on a real line is called a real number. These numbers can be positive, negative, or zero. The real number system is denoted in a set notation by the symbol R.
Properties of Real Numbers
Real numbers have certain fundamental properties that make them unique. These properties are defined as follows:
Closure: The real numbers are closed under addition, subtraction, multiplication, and division. This means that when two real numbers are added, subtracted, multiplied or divided, the result will always be a real number.
Commutative Property: The commutative property applies to addition and multiplication. This means that when two real numbers are added or multiplied, the order in which the operation is performed does not affect the result.
Associative Property: The associative property applies to addition and multiplication. This means that when three or more real numbers are added or multiplied, the way the parenthesis are arranged does not affect the result.
Identity Property: The identity property applies to addition and multiplication. This means that adding or multiplying a real number by zero does not change the value of the number. The identity element for addition is zero, and the identity element for multiplication is one.
Inverse Property: The inverse property applies to addition and multiplication. This means that every real number has an additive inverse, which is the opposite of the number, and a multiplicative inverse, which is the reciprocal of the number. The inverse element for addition is the opposite of the number, and the inverse element for multiplication is the reciprocal of the number.
Distributive Property: The distributive property applies to addition and multiplication. This means that when a real number is multiplied by the sum of two other real numbers, the result can be obtained by multiplying each term of the sum by that number and then adding the products.
Types of Real Numbers
Real numbers can be classified into different types based on their nature. The following are the types of real numbers:
1. Positive Real Numbers: These numbers are greater than zero and are denoted by R+.
2. Negative Real Numbers: These numbers are less than zero and are denoted by R-.
3. Whole Numbers: These numbers are all positive integers including zero.
4. Integers: These numbers are all positive and negative integers including zero.
5. Rational Numbers: These numbers can be expressed as a ratio of two integers.
6. Irrational Numbers: These numbers cannot be expressed in the form of a ratio of two integers.
Applications of Real Numbers
The real number system has several practical applications. Some of these applications include:
1. Measuring distances on a real line.
2. Measuring time on a clock.
3. Measuring temperature on a thermometer.
4. Calculating the speed of objects in motion.
5. Measuring the area and volume of objects.
Conclusion
Real numbers are the foundation of the mathematical world. They have unique properties that make them essential to mathematical operations. The different types of real numbers have various applications in real life situations. Therefore, understanding the real number system is vital for mastering mathematics and its real world applications.