Question

Write the rationalisting factor of 7÷3+√8​

Answer 1

4

Step-by-step explanation:

Rationalising factor is a term with which an irrational number gives a rational number after multiplication.

Also, If we have a number a + b√c then its Rationalising factor will be a - b√c,

Similarly, for a - b√c, Rationalising factor will be a + b√c ,

Here, the given irrational number is,

7 - 3√5,

Thus, by the above definition,

The rationalising factor of 7 - 3√5 is 7 + 3√5.

Verification :

(7 - 3√5 ) . ( 7 + 3√5 ) = 7² - (3√5)² = 49 - 45 = 4.