Rational and Irrational Numbers
ICSE · Class 9 · Mathematics
Summary of Rational and Irrational Numbers for ICSE Class 9 Mathematics. Key concepts, important points, and chapter overview.
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Rational numbers, irrational numbers, and real numbers form the basic structure of the complete number system up to real numbers. Rational numbers can be written as a/b where a and b are integers and b is not zero. They include integers, terminating decimals, and recurring decimals. Irrational numbe
Key Concepts
A number that can be expressed
A number that can be expressed as a/b, where a and b are integers and b is not zero, is a rational number. Every integer and every decimal number is r
Irrational numbers are non
Irrational numbers are non-terminating, non-recurring decimals and cannot be written as p/q. Square roots, cube roots, and similar roots are irrationa
The set of real numbers
The set of real numbers is the union of rational numbers and irrational numbers, written as R = Q ∪ Q̄.
A terminating decimal ends after
A terminating decimal ends after a finite number of digits. A recurring decimal repeats one digit or a block of digits continuously. A mixed recurring
A rational number has a terminating
A rational number has a terminating decimal form when its denominator can be written as 2^m × 5^n, where m and n are whole numbers.
Learning Objectives
- Identify rational and irrational numbers correctly
- Write rational numbers in fraction and decimal form
- Use methods to find numbers between two given rational numbers
- Convert recurring decimals into fractions
- Recognize terminating and non-terminating decimal patterns
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