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Class 9 (Assamese)

Course: Class 9 (Assamese)>Unit 1

Lesson 1: Irrational numbers

Classifying numbers

There are four categories in which numbers can be claified in. These categories include rational numbers, irrational numbers, integers, and whole numbers. Rational numbers are represented as a fraction of two integers, while irrational numbers cannot be represented as a fraction of two integers. Integers are numbers that don't have to be represented as a fraction or a decimal and a subset of integers are whole numbers, which are non-negative integers.

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• can someone give me a summary of natural numbers, whole numbers, integers, rational numbers ad irrational number please? i'm still kinda confused because i'm not sure about the differences between them
• Natural numbers:
all the whole numbers except 0

Whole numbers:
all of the counting numbers (1, 2, 3, etc.) plus 0

Integers:
(can be positive or negative)
all of the whole numbers (1, 2, 3, etc.) plus all of their opposites (-1, -2, -3, etc.) and also 0

Rational numbers:
any number that can be expressed as a fraction of two integers (like 92, -56/3, √25, or any other number with a repeating or terminating decimal)

Irrational numbers:
all the numbers that can't be expressed as a fraction of two integers (like π, √7, or any other number with a non-repeating & non-terminating decimal)

Hope this helps!
• Why is 0 considered rational if 0/0 is undefined? i guess it can be integer because its sign neutral. I would assume its just a whole number and an integer.
• The fact that 0 can be written as 0/1 is enough to show that 0 is rational.
• wait, aren't whole numbers literally the same thing as integers? and inside integers you have natural numbers, so it'd be, reals => rational and irrational, within rational => integers => natural numbers and then outside reals, complex.

how are whole numbers in any way different from integers? or natural, for that matter? or is it just a different name? but N is used for them, so it should be "natural", still.
• natural numbers contains just the positive numbers.
whole numbers are different as they contain zero in addition.
Integers are also different they contain negative numbers ,positive numbers and 0.
• You might think I am using a form of reverse psychology but I’m not…. Do not vote for me. …. Or am I.
• ok ill downvote dw
(1 vote)
• How is pie over pie one!?!?!!?!?!?! Pie is inf
• While pi has an infinite number of decimal digits, pi is overall still a finite number because pi is between 3 and 4.

Any nonzero, finite number divided by itself is 1.

So pi / pi = 1.

Have a blessed, wonderful day!
• why in gods holy begotten name is this so overcomplicated
• What about natural numbers, and real numbers? What are those?
• Natural numbers are just positive integers (1,2,3,4,5,6,7 etc)
Real numbers are every single type of number (fractions, decimals, irrational numbers, basically anything) Best of Luck!!
• Why arn't negatives considered Whole numbers if they are numbers
• Just because something is a number doesn’t mean that it has to be a whole number. Fractions, decimals, and negatives are all numbers, but they are not whole numbers. A whole number is required to be 0 or greater and without fractional or decimal part.

Numbers without fractional or decimal part are called integers, but negative integers are not considered whole numbers.

Have a blessed, wonderful day!
• Hold on a minute... At Sal said 22/7 is a rational number. Isn't 22/7 pi (an irrational number)? Did he make a mistake or did I?
• 22/7 is a rational number, but it is only an approximation of pi just like 3.14 is. Put pi and 22/7 in the calculator and you will see they are not exactly the same.
• Doesn't it mean that integers are only negative?
• Integers are 1,2,3,4,5,6,7,8,9, e.t.c. They can also be negative, but-