





Maths Crash Course - Live lectures + all videos + Real time Doubt solving!
Examples
Example 1 (ii)
Example 1 (iii) Important
Example 2
Example 3
Example 4 Important
Example 5
Example 6
Example 7 Important Deleted for CBSE Board 2023 Exams
Example 8
Example 9 Important Deleted for CBSE Board 2023 Exams
Example 10 Important Deleted for CBSE Board 2023 Exams
Example 11
Example 12 Important You are here
Example 13
Example 14
Example 15 Important
Example 16 (i) Important Deleted for CBSE Board 2023 Exams
Example 16 (ii)
Example 16 (iii)
Example 16 (iv)
Example 17
Example 18
Example 19 Deleted for CBSE Board 2023 Exams
Example 20 Important
Example 21 (i) Deleted for CBSE Board 2023 Exams
Example 21 (ii)
Example 21 (iii) Important
Example 21 (iv) Important
Last updated at Aug. 24, 2021 by Teachoo
Maths Crash Course - Live lectures + all videos + Real time Doubt solving!
Example 12(Method 1) Check whether 7 5, 7/ 5, 2 + 21, 2 are irrational numbers or not. 7 7 is rational 5 = 2.236 . which is non- terminating non-repeating is an irrational number We know that Rational Irrational = Irrational Since, 7 5 = 7 5 it is irrational / 7 is rational 5 = 2.236 . which is non- terminating non-repeating is an irrational number We know that / = Irrational Thus, 7/ 5 is irrational + 21 21 is rational 2 " = 1.4142 " which is non- terminating non-repeating is an irrational number We know that Irrational + Rational = Irrational Thus, 2 + 21 is an irrational number 2 2 is rational = 3.1415 . which is non- terminating non-repeating is an irrational number We know that Irrational Rational = Irrational Thus, - 2 is an irrational number Example 12 (Method 2) Check whether 7 5, 7/ 5, 2 + 21, 2 are irrational numbers or not. 7 5 = 2.236 . 7 5 = 7 (2.346) = 15.652 .., It is a non-terminating and non-repeating decimal expansion. So,7 5 is an irrational number / 7/ 5 = (7 5)/( 5 5) = (7 5)/5 = 7/5 (2.346) = 3.1304 . It is a non-terminating and non-repeating decimal expansion. So, 7/ 5 is an irrational number + 21 2 = 1.4142 2 + 21 = 1.4142 + 21 = 22.4142 , It is a non-terminating and non-repeating decimal expansion. So, 2 + 21 is an irrational number 2 = 3.1415 . 2 = 3.1415 . 2 = 1.1415 It is a non-terminating and non-repeating decimal expansion. So, - 2 is an irrational number