If you square the square root of a number, you end up with the number itself.
Hmm…that sounds a little confusing. Let’s see this one in action.
We’re going to begin with √9.
Now let’s square it. (√9)2. This is the same as saying: √9 * √9
Because we happen to know our perfect squares (You do know your perfect squares through 202, right?), we know that √9 = 3.
We plug the 3 back into our equation every time we see a √9, and we get 3 * 3, which equals 9.
For those of you familiar with radical expressions, let’s try this one more time. √9 is the same as 9½.
When we square it this time, it looks like this: (9½)2.
We have a law of exponents that says when we raise a power to another power, we simply multiply the two together to get the new exponent. In this case, we’re multiplying 2 and ½ which equals 1. Our problem now looks like this: 91.
Any number raised to the power of 1 is itself, so our answer is 9.
