Rationalise the denominators each of the following :

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Chapter 1 NCERT Class 9 Mathematics SOLUTIONS

5. Rationalise the denominators each of the following :

Question:

Rationalise the denominators each of the following :

1. 1/√7

Answer:

1/√7

Multiplying numerator and denominator by √7

∴ 1/√7 =1/√7 × √7/√7 = √7/7

More NCERT Questions

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(All Q's of this Chapter solved)

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Classify the following numbers as rational or irrational: (i) 2 − √5

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Express the following in the form p/q , where p and q are integers and q ≠ 0 :

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You know that 1/7 = 0.142857 . Can you predict what the decimal expansions of 2/7 , 3/7 , 4/7 , 5/7 , 6/7 are, without actually doing the long division ? If yes, how ?

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Write the following in decimal form and say what kind of decimal expansion each has :

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Classroom activity (Constructing the ‘square root spiral’) : Take a large sheet of paper and construct the ‘square root spiral’ in the following fashion.

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Show how √5 can be represented on the number line.

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Are the square roots of all positive integers irrational? If not, give an example of the square root of a number that is a rational number.

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State whether the following statements are true or false. Give reasons for your answers.

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3. Find five rational numbers between 3/5 and 4/5.

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Find six rational numbers between 3 and 4.

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Is zero a rational number ? Can you write it in the form p q , where p and q are integers and q ≠ 0 ?

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