Question

2√2/√5 rationalse the denominator

Answer 1

When we rational we need to multiply √5 on the numerator and denominator

=2√2/√5×√5/√5

=2√10/5

Answer 2

Answer- The above question is from the chapter 'Number System'.

Let's know about rational numbers, irrational numbers and rationalising.

Rational Numbers- Numbers which can be written in the form of p/q where p,q are integers and q ≠ 0.

Decimal expansion of rational numbers is always terminating or non-terminating but repeating.

Example: 0, 2/3, -4/7, 2.1212..., etc.

Irrational Numbers- Numbers which can't be written in the form of p/q.

Decimal expansion of irrational numbers is always non-terminating non- repeating.

Example: π, √3, √7, 2.343443444..., etc.

Rationalising is basically done to convert the root in the denominator to whole number.

Given question: Rationalise the denominator- 2√2/√5.

Solution: Numerator =  2√2

Denominator = √5

Rationalising factor of √5 = √5 since √5 multiplied by √5 is equal to 5 which is a whole number.

2√2/√5 = 2√2/√5 × √5/√5

              =  2√2 × √5/5

              =  2√10/5

So, the answer is  2√10/5.