Unlocking the Mystery of Square Roots

Get ready to dive into the fascinating world of square roots! These mathematical marvels have captivated the minds of brilliant thinkers for centuries, and for good reason. Not only are they crucial in understanding the basics of geometry, but they also have countless applications in the scientific and engineering fields.

For centuries, humans have been fascinated by the power of square roots. From ancient civilizations to modern-day mathematicians, we’ve used square roots to unlock the secrets of geometry and beyond. Take, for example, a triangle with sides of equal length – let’s say 1 centimeter each. What’s the length of the third side, you ask? Well, that’s where the magic of square roots comes in. By applying the Pythagorean relation, we can determine that the length of the third side, let’s call it $a$, is equal to the square root of 2. But here’s where things get really interesting – mathematicians have shown that this number, $\sqrt{2}$, is not a rational number. Nope, it’s a real number, and in this section, we’re going to dive deep into the fascinating world of these types of numbers. So buckle up, folks – it’s going to be a wild ride!

In this article, we’ll take a comprehensive journey through the world of square roots. We’ll start by defining what they are and exploring their properties. Then, we’ll delve into the exciting ways they’re used in both mathematics and the real world.

What is a square number?

A square number, also known as a perfect square, is a number that can be expressed as the product of another number multiplied by itself. In mathematical notation, if ‘a’ is a number, then ‘$a^2$’ represents a square number. In fact, a square is just a number $a$ with exponent $2$.

For example, 9 is a square number because it can be expressed as $3^2$, 3 multiplied by 3. Square numbers have the property that when their square root is taken, the result is a whole number.

What is a square root of positive numbers?

So, what exactly is a square root? At its core, it’s a value that, when multiplied by itself, gives you the original number. We use the symbol $\sqrt{b}$ to represent the square root of a non-negative number ‘$b$’. Sometimes we also use the notation $b^{\frac{1}{2}}$ for the square root. It’s important to note that square roots of negative numbers are considered complex numbers and are beyond the scope of this article. Are you ready to explore the world of square roots? Let’s get started!

The following rule is important:

If $a$ is a postive number, then $$\sqrt{a^2}= a.$$ $\blacktriangleright$ Examples: +
The square root of 4 is calculated as: $\sqrt{4}=\sqrt{2^2}= 2$. Observe that $\sqrt{0}=\sqrt{0^2}= 0$ and $\sqrt{1}=\sqrt{1^2}= 1$.

Basic properties of square roots

If $a$ and $b$ are positive numbers, then square root of the product $ab$ is given by $$\sqrt{ab}=\sqrt{a}\times \sqrt{b}.$$ $\blacktriangleright$ Examples: +
$ \sqrt{12}=\sqrt{4\times 3}=\sqrt{4}\times \sqrt{3}=2\sqrt{3}$.
For a positive number $b$ the solutions of the quadratic equation $x^2=b$ are: \begin{align*}x=\sqrt{b}\quad\text{or}\quad x=-\sqrt{b},\end{align*} $\blacktriangleright$ Details: +

Are you ready to unlock the secrets of solving quadratic equations? Let’s dive in! First, let’s take a look at the equation $x^2=b$. We can rewrite this as $x^2-(\sqrt{b})^2=0$, which is equivalent to $(x-\sqrt{b})(x+\sqrt{b})=0$. This means that either $x-\sqrt{b}=0$ or $x+\sqrt{b}=0$, giving us the solutions $x=\sqrt{b}$ or $x=-\sqrt{b}$.

Now, let’s put this knowledge to the test and solve the equation $x^2=144$. It’s as easy as computing the square root of 144, which is 12. But wait, there’s more! We can simplify even further by breaking down $\sqrt{144}$ into $\sqrt{4\times 36}$. This gives us $\sqrt{4}\times \sqrt{36}$, which equals 2 times 6. Therefore, the solutions to the equation are $x=12$ or $x=-12$.

See how easy it is to solve quadratic equations? With a little bit of algebraic manipulation and some clever simplification, you can unlock the solutions to even the most complex equations. Keep practicing and soon you’ll be a quadratic equation-solving master!

Square Root of a Fraction $$ \sqrt{\frac{p}{q}}=\frac{\sqrt{p}}{\sqrt{q}}.$$ $\blacktriangleright$ Examples: +
Calculate $\sqrt{\frac{4}{9}}$. We have $$ \sqrt{\frac{4}{9}}= \frac{\sqrt{4}}{\sqrt{9}}=\frac{\sqrt{2^2}}{\sqrt{3^2}}=\frac{2}{3}.$$ Determine $\frac{\sqrt{12}}{\sqrt{3}}$. We have $$\frac{\sqrt{12}}{\sqrt{3}}=\sqrt{\frac{12}{3}}=\sqrt{4}=2.$$

Did you know that in the world of mathematics, it’s a well-known fact that square roots should never be left hanging out in the denominator of a number? Yup, it’s true! So if you want to impress your math teacher or your friends, make sure to always simplify those pesky square roots. Trust us, it’ll make your life a whole lot easier!

Simplify the following numbers $$ \frac{1}{\sqrt{2}},\quad \frac{2}{\sqrt{5}}.$$ $\blacktriangleright$ Details: +
Multiplying the denominator by the same square root number! It’s like casting a spell that transforms the equation into a simpler, more manageable form. In fact $$\frac{1}{\sqrt{2}}= \frac{\sqrt{2}}{\sqrt{2}\times \sqrt{2}}=\frac{\sqrt{2}}{2}.$$ In addition $$ \frac{2}{\sqrt{5}}=\frac{2\sqrt{5}}{\sqrt{5}\times \sqrt{5}}=\frac{2\sqrt{5}}{5}.$$
For positive numbers $a$ and $b$, $$ (\sqrt{a}+\sqrt{b})(\sqrt{a}+\sqrt{b})=a-b.$$ $\blacktriangleright$ Details: +
We calculate \begin{align*} (\sqrt{a}+\sqrt{b})(\sqrt{a}+\sqrt{b})&=(\sqrt{a})^2-\sqrt{a}\times \sqrt{b}+\sqrt{a}\times \sqrt{b}-(\sqrt{b})^2\cr &= a-b.\end{align*}
Simplify the number $$ \frac{1}{\sqrt{3}+\sqrt{2}}.$$ $\blacktriangleright$ Details: +
We calculate \begin{align*} \frac{1}{\sqrt{3}+\sqrt{2}}&=\frac{\sqrt{3}-\sqrt{2}}{(\sqrt{3}+\sqrt{2})(\sqrt{3}-\sqrt{2})}\cr &=\frac{\sqrt{3}-\sqrt{2}}{3-2}\cr &=\sqrt{3}-\sqrt{2}.\end{align*}

Applications of this class of numbers

Are you ready to discover the power of square roots? From geometry to computer graphics, these little symbols have a big impact on a variety of fields. In geometry, the Pythagorean theorem relies on square roots to solve problems involving right-angled triangles. Engineers and physicists use square roots to calculate everything from velocity to electrical voltage. In statistics and probability, square roots help calculate standard deviations and confidence intervals. Furthermore, in finance and investment, square roots are essential for calculating risk and volatility. Even computer graphics rely on square roots to calculate distances, angles, and transformations in virtual environments. So next time you see that little symbol, remember the big impact it can have in so many different areas.


Did you know that square roots are more than just boring math concepts? They’re actually super important tools that have practical applications in all sorts of fields! From geometry to finance, these little symbols help us understand the world around us and solve complex problems. So next time you come across the √ symbol, don’t just brush it off as another math thing. It’s actually the key to unlocking a whole world of possibilities and real-world applications. Square roots are the foundation of math and science, and they enrich our lives in ways we might not even realize. Pretty cool, huh?

Subscribe our newsletter

  • Unlimited access to all
  • Paper Magazine delivery
  • Priority Support
Thank You, we'll be in touch soon.

Share article


StateMath: Your go-to blog for all things math! Explore our wide range of courses and exercises on algebra, calculus, probability, and geometry. Let's ace those math problems together!