Question

Rationalise the denominators of the following 1/root7-2​

Answer 1

Answer:

firstly, change the sign of the denominator , i.e √7 - √2 will become √7 + 2 , so multiply this term both with numerator and denominator. Multiply the terms , and we know that (a+b)(a-b) = a² - b² , use this identity for denominator! solve it more , square root and square will cancel out

Answer 2

Step-by-step explanation:

1/Root7 -2 => 1/ root7 -2 × 1/root7 + 2

=> 1 × (root 7 + 2)/ (root7)^2 - (2)^2

=> root 7 + 2/ 7 - 4

=> root 7 + 2/ 3

Thus the rationalized number is root 7 + 2/ 3

Hope it helps champ:)