Question

Which of the following is an irrational number?
(1) 3+√2
(2) √4+2
(3) 3+√9
(4) 2√6 - √24​

Answer 1

Answer:

Only the square roots of the square numbers, i.e. the square roots of the perfect square is rational number.

(i) In 2−

5

, the number

5

is not a rational number, then 2−

5

is a irrational number.

(ii) In (3+

23

)−

23

=3+

23

−

23

=3 is a rational number.

(iii)

7

7

2

7

=

7

2

is a rational number.

(iv) In

2

1

, the number

2

is not a rational number, then

2

1

is irrational number.

(v) π is an irrational number, hence 2π is an irrational number.

Answer 2

Answer:

1 and 4 is irrational number