Question

Which numbers are irrational?

Choose all answers that are correct.

Answer 1

The first two. In fact, you have

`√(20) = √(4\cdot 5) = √(4)\cdot √(5) = 2√(5)`

and
`√(5)` is irrational.

Similarly,
`\pi` is irrational, and the same goes for
`4\pi`.

Instead, the square root and the second power simplify in the third option:

`\left(√(13)\right)^2 = 13`

and similarly,

`√(196) = √(14^2) = 14`