Question

How do you simplify `4/sqrt5`?

Answer 1

`4/5sqrt5`

Explanation:

We require to `color(blue)"rationalise the denominator"`

To do this, multiply the numerator and denominator by `sqrt5`

`"Since " sqrt5xxsqrt5=5" a rational number"`

`rArr4/sqrt5=4/sqrt5xxsqrt5/sqrt5=(4sqrt5)/5=4/5sqrt5`