Book: RS Aggarwal & V Aggarwal - Mathematics
Chapter: 1. Real Number
Subject: Mathematics - Class 9th
Q. No. 40 of CCE Questions
Listen NCERT Audio Books to boost your productivity and retention power by 2X.
Give an example of two irrational numbers whose sum as well as the product is rational.
Let two irrational numbers be 10 + 2√5 and 5 - 2√5
(i) sum is rational
= 10 + 2√5 + 5 - 2√5
= 15 (a rational number)
(ii) product is rational are
= (10 + 2√5) (10 - 2√5)
= (10)2 - (2√5)2
= 100 - 20 = 80 (a rational number)
Chapter Exercises
More Exercise Questions
The question consists of two statements, namely, Assertion (A) and Reason (R). Please select the correct answer.
Assertion (A) | Reason (R) |
The rational numbers between | A rational number between two rational numbers p and q is |
The question consists of two statements, namely, Assertion (A) and Reason (R). Please select the correct answer.
Assertion (A) | Reason (R) |
| Square root of a positive integer which is not a perfect square is an irrational number. |
The question consists of two statements, namely, Assertion (A) and Reason (R). Please select the correct answer.
Assertion (A) | Reason (R) |
e is an irrational number. |
|
The question consists of two statements, namely, Assertion (A) and Reason (R). Please select the correct answer.
Assertion (A) | Reason (R) |
| The sum of a rational number and an irrational number is an irrational number. |
Match the following columns:
Column I | Column II |
A. B. C. The length of period of D. If | (p) 14 (q) 6 (r) a rational number (s) an irrational number |
The correct answer is:
(a)-……., (b)-……., (c)-……., (d)-…….,
Match the following columns:
Column I | Column II |
A. B. C. D. | (p) 4 (q) (r) (s) 3 |
The correct answer is:
(a)-……., (b)-……., (c)-……., (d)-…….,
If 
and 
find 
and find 
if 
show that 
show that if 
show that 
show that if 
show that 
show that if 
show that 
show that 
