Question

rationalise 1/7+root 2​

Answer 1

Step-by-step explanation:

$= \frac{1}{7 + \sqrt{2} } \\ \\ = \frac{1}{ 7 + \sqrt{2} } \times \frac{7 - \sqrt{2} }{7 - \sqrt{2} } \\ \\ = \frac{7 - \sqrt{2} }{49 - 2} \\ \\ = \frac{7 - \sqrt{2} }{47}$

Answer 2

Step-by-step explanation:

firstly, change the sign of the denominator , i.e √7 - √2 will become √7 + 2 , so multiply this term both with numerator and denominator.

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Multiply the terms , and we know that (a+b)(a-b) = a² - b² , use this identity for denominator!

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solve it more , square root and square will cancel out!

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thus , after rationalising we will get :-

$(\sqrt{7 + 2} ) \div 3$