Question

If x = 5 - √7 , find the reciprocal of x with rational denominator.​

Answer 1

Answer:

Step-by-step explanation:

x = 5 - √7

Reciprocal of x:

1/5 - √7

Rationalising the denominator

1/5 - √7 × 5 + √7/5 + √7

= 5 + √7/(5-√7) (5+√7)

= 5 + √7/ 5² - (√7)²

= 5 + √7/ 25 - 7

= 5 + √7/18