Question

Write the lowest rationalizing factor of :
15-3√2​

Answer 1

Given: The term 15-3√2​

To find: The lowest rationalizing factor.

Solution:

• Now we know that :

• Rationalizing factor is a term with which a term is multiplied or divided to make the whole term rational.

• So we have given 15-3√2​.

• Taking 3 common, we get:

               3 ( 5 - √2 )

• Now multiplying it with ( 5 + √2 ) to rationalize, we get:

               3 ( 5 - √2 ) x ( 5 + √2 )

• Now using formula: a^2 - b^2 = (a-b)(a+b)

               3 x (5^2 - √2^2)

               3 x (25 - 2)

               3 x 23

               69

Answer:

           So the  lowest rationalizing factor of 15-3√2​ is ( 5 + √2 ).