Book: RS Aggarwal & V Aggarwal - Mathematics
Chapter: 1. Real Number
Subject: Mathematics - Class 9th
Q. No. 40 of CCE Questions
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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)-…….,
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