Question

How do you find √25√81?

Answer 1

Prime factorisation of 25 gives 5×5. Grouping the factors by taking two at a time gives the square root. So 5 is the root of 25.

Prime factorisation of 81 gives 3×3×3×3. Grouping the factors by taking two at a time gives 3×3 which is 9. So 9 is the root of 81.