Introduction to squares and square roots

From Karnataka Open Educational Resources

As we are already familiar with numbers and different types of number,let us try to understand what is square and square root. As soon as we listen to square, what comes to or mind is the geometrical shape called square where all the sides are equal, now are we really going to learn about the geometrical shape square, actually not but we can try to co-relate in understanding the meaning of square number and square root with the help of a figure.

We can observe the geometrical shape square which is having equal sides of 3 cm each.

Now let us divide each sides of square with 1cm each on both sides by forming the grids.

We also observe that there are 3x3 grids and totally we have 9 grids.

If a square measures 3cm how do we find its area?

We multiply the side x sides which gives area of a square similarly the length of a square is measured as 3cm, then

Area= 3 x 3=9

As 9 cm^2 is the area, we can also observe in the figure that a square has total 9 grids which gives the square of the taken length.

In mathematics, a square is the result of multiplying a number by itself. The verb "to square" is used to denote this operation. Squaring is the same as raising to the power 2, and it is denoted by a superscript 2; for instance, the square of any number can be written as 3^2 which is the number 9

The square number and square root are exactly inverse operation in mathematics.

The square root of a number x is y such that y^2=x;in other words a number y whose square gives the square root of x.

The square root is usually denoted as

Sqrt.png


From the above square let us try to understand the square root of a number

As the area of a square is 9 in order to write it as side x side, it can be written as 3 x 3.

such that square root of 9 will be the side of the length 3.