MATH7

Let us see if you still know how to square a number.

Take a look at this unusual wall clock and answer the questions

The radicand 1, 4, 9, 16, 36, and 81 are perfect square numbers.

As you can see, every non-zero real number has 2 square roots, one positive and one negative. The positive square root of positive real numbers is the principal square root of that number.

Notice also, that the square root of perfect square numbers is rational numbers. Rational numbers are numbers that can be expressed as a ratio or quotient of two integers, where the denominator is not zero.

Choose “rational” if the principal root of each of the following numbers is a rational number and “ irrational” if it is not . If it is rational give its principal root.