Question

How can we use radicals in real life?

Answer 1

European paper sizes are a good example of real world usage of a radical.

The ratio of the length of the longer side of A4 paper to the shorter side is a good approximation of `sqrt(2)`. As a result, a sheet of A4 can be cut in half to produce two smaller sheets (size A5) with the same proportions as the A4 sheet.

Answer 2

Another real life example would be calculation of interest rates.

If the annual interest rate on your savings is `3%` then the monthly interest rate would be:

`(root(12)1.03 - 1.0)*100%`