**Square Roots and Square-Root Functions**

When we raise a number to the second power, we say that we have **squared**

the number. Sometimes we may need to find the number that was squared.

We call this process **finding a square root **of a number.

**SQUARE ROOT**

The number *c *is a **square root **of *a *if c^{2} = a.

**PROPERTIES OF SQUARE ROOTS**

Every positive real number has two real-number square roots.

The number 0 has just one square root, 0 itself.

Negative numbers do not have real-number square roots.*

**PRINCIPAL SQUARE ROOT**

The **principal square root **of a nonnegative number is its nonnegative

square root. The symbol √a represents the principal square root of *a*.

To name the negative square root of *a*, we can write – √a .