Hey there! We receieved your request
Stay Tuned as we are going to contact you within 1 Hour
One of our academic counsellors will contact you within 1 working day.
Click to Chat
1800-5470-145
+91 7353221155
Use Coupon: CART20 and get 20% off on all online Study Material
Complete Your Registration (Step 2 of 2 )
Sit and relax as our customer representative will contact you within 1 business day
OTP to be sent to Change
Non-negative counting numbers excluding zero are called Natural Numbers.
N = 1, 2, 3, 4, 5, ……….
All natural numbers including zero are called Whole Numbers.
W = 0, 1, 2, 3, 4, 5, …………….
All natural numbers, negative numbers and 0, together are called Integers.
Z = – 3, – 2, – 1, 0, 1, 2, 3, 4, …………..
The number ‘a’ is called Rational if it can be written in the form of r/s where ‘r’ and ‘s’ are integers and s ≠ 0,
Q = 2/3, 3/5, etc. all are rational numbers.
To find the rational number between two given numbers ‘a’ and ‘b’.
Example:
Find 2 rational numbers between 4 and 5.
Solution:
To find the rational number between 4 and 5
To find another number we will follow the same process again.
Hence the two rational numbers between 4 and 5 are 9/2 and 17/4.
Remark: There could be unlimited rational numbers between any two rational numbers.
The number ‘a’ which cannot be written in the form of p/q is called irrational, where p and q are integers and q ≠ 0 or you can say that the numbers which are not rational are called Irrational Numbers.
Example - √7, √11 etc.
All numbers including both rational and irrational numbers are called Real Numbers.
R = – 2, – (2/3), 0, 3 and √2
1. Rational Numbers
If the rational number is in the form of a/b then by dividing a by b we can get two situations.
a. If the remainder becomes zero
While dividing if we get zero as the remainder after some steps then the decimal expansion of such number is called terminating.
7/8 = 0.875
b. If the remainder does not become zero
While dividing if the decimal expansion continues and not becomes zero then it is called non-terminating or repeating expansion.
1/3 = 0.3333….
Hence, the decimal expansion of rational numbers could be terminating or non-terminating recurring and vice-versa.
2. Irrational Numbers
If we do the decimal expansion of an irrational number then it would be non –terminating non-recurring and vice-versa. i. e. the remainder does not become zero and also not repeated.
π = 3.141592653589793238……
To represent the real numbers on the number line we use the process of successive magnification in which we visualize the numbers through a magnifying glass on the number line.
Step 1: The number lies between 4 and 5, so we divide it into 10 equal parts. Now for the first decimal place, we will mark the number between 4.2 and 4.3.
Step 2: Now we will divide it into 10 equal parts again. The second decimal place will be between 4.26 and 4.27.
Step 3: Now we will again divide it into 10 equal parts. The third decimal place will be between 4.262 and 4.263.
Step 4: By doing the same process again we will mark the point at 4.2626.
1. The sum, difference, product and quotient of two rational numbers will be rational.
2. If we add or subtract a rational number with an irrational number then the outcome will be irrational.
If 5 is a rational number and √7 is an irrational number then 5 + √7 and 5 - √7 are irrational numbers.
3. If we multiply or divide a non-zero rational number with an irrational number then also the outcome will be irrational.
If 7 is a rational number and √5 is an irrational number then 7√7 and 7/√5 are irrational numbers.
4. The sum, difference, product and quotient of two irrational numbers could be rational or irrational.
To find √x geometrically
1. First of all, mark the distance x unit from point A on the line so that AB = x unit.
2. From B mark a point C with the distance of 1 unit, so that BC = 1 unit.
3. Take the midpoint of AC and mark it as O. Then take OC as the radius and draw a semicircle.
4. From the point B draw a perpendicular BD which intersects the semicircle at point D.
The length of BD = √x.
To mark the position of √x on the number line, we will take AC as the number line, with B as zero. So C is point 1 on the number line.
Now we will take B as the centre and BD as the radius, and draw the arc on the number line at point E.
Now E is √x on the number line.
If p and q are two positive real numbers
Examples:
1. Simplify
We will use the identity
2. Simplify
Rationalize the denominator means to convert the denominator containing square root term into a rational number by finding the equivalent fraction of the given fraction.
For which we can use the identities of the real numbers.
Rationalize the denominator of 7/(7- √3).
We will use the identityhere.
If we have a and b as the base and m and n as the exponents, then
1. a^{m} × a^{n} =a^{m+n}
^{ }2. (a^{m})^{n} = a^{mn}
4. a^{m }b^{m} = (ab)^{m}
5.^{ }a^{0} = 1
6. a^{1} = a
7. 1/a^{n} = a^{-n}
Let a > 0 be a real number and n a positive integer.
Let a > 0 be a real number. Let m and n be integers such that m and n have no common factors other than 1, and n > 0. Then,
Simplify the expression (2x^{3}y^{4}) (3xy^{5})^{2}.
Here we will use the law of exponents
a^{m} × a^{n} =a^{m+n} and (a^{m})^{n} = a^{mn}
(2x^{3}y^{4})(3xy^{5})^{2}
(2x^{3}y^{4})(3 ^{2} x ^{2} y^{10})
18. x^{3}. x^{2}. y^{4}. y^{10}
18. x^{3+2}. y^{4+10}
18x^{5}y^{14}
Revision Notes on Probability Probability...
Revision Notes on Areas of Parallelograms and...
Statistics CBSE Class 9 Science Revision Notes...
Revision Notes on Coordinate Geometry Cartesian...
Revision Notes on Lines and Angles Basic terms and...
Revision Notes on Circles Introduction to Circles...
Revision Notes on Triangles Triangle A closed...
Revision Notes on Constructions Introduction to...
Revision Notes on Linear Equations in Two...
Revision Notes on Polynomials Polynomial...
Revision Notes on Surface Areas and Volumes Plane...
Revision Notes on Introduction to Euclid’s...
Revision Notes on Heron’s Formula Perimeter...
Revision Notes on Quadrilaterals Quadrilateral Any...