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Example Questions
Example Question #3 : Simplifying Square Roots
What is equal to?
1. We know that , which we can separate under the square root:
2. 144 can be taken out since it is a perfect square: . This leaves us with:
This cannot be simplified any further.
Example Question #5 : Simplifying Square Roots
Which of the following is equal to ?
When simplifying square roots, begin by prime factoring the number in question. For , this is:
Now, for each pair of numbers, you can remove that number from the square root. Thus, you can say:
Another way to think of this is to rewrite as . This can be simplified in the same manner.
Example Question #2 : Simplifying Square Roots
Which of the following is equivalent to ?
When simplifying square roots, begin by prime factoring the number in question. This is a bit harder for . Start by dividing out :
Now, is divisible by , so:
is a little bit harder, but it is also divisible by , so:
With some careful testing, you will see that
Thus, we can say:
Now, for each pair of numbers, you can remove that number from the square root. Thus, you can say:
Another way to think of this is to rewrite as . This can be simplified in the same manner.
Example Question #72 : Arithmetic
What is the simplified (reduced) form of ?
It cannot be simplified further.
To simplify a square root, you have to factor the number and look for pairs. Whenever there is a pair of factors (for example two twos), you pull one to the outside.
Thus when you factor 96 you get
Example Question #3 : Simplifying Square Roots
Which of the following is equal to ?
When simplifying square roots, begin by prime factoring the number in question. For , this is:
Now, for each pair of numbers, you can remove that number from the square root. Thus, you can say:
Another way to think of this is to rewrite as . This can be simplified in the same manner.
Example Question #51 : Basic Squaring / Square Roots
Simplify the following square root:
The square root is already in simplest form.
The square root is already in simplest form.
We need to factor the number in the square root and find pairs of factors inorder to simplify a square root.
Since 83 is prime, it cannot be factored.
Thus the square root is already simplified.
Example Question #12 : Simplifying Square Roots
Right triangle has legs of length . What is the exact length of the hypotenuse?
If the triangle is a right triangle, then it follows the Pythagorean Theorem. Therefore:
--->
At this point, factor out the greatest perfect square from our radical:
Simplify the perfect square, then repeat the process if necessary.
Since is a prime number, we are finished!
Example Question #13 : Simplifying Square Roots
Simplify:
There are two ways to solve this problem. If you happen to have it memorized that is the perfect square of , then gives a fast solution.
If you haven't memorized perfect squares that high, a fairly fast method can still be achieved by following the rule that any integer that ends in is divisible by , a perfect square.
Now, we can use this rule again:
Remember that we multiply numbers that are factored out of a radical.
The last step is fairly obvious, as there is only one choice:
Example Question #14 : Simplifying Square Roots
Simplify:
A good method for simplifying square roots when you're not sure where to begin is to divide by , or , as one of these generally starts you on the right path. In this case, since our number ends in , let's divide by :
As it turns out, is a perfect square!
Example Question #15 : Simplifying Square Roots
Simplify:
Again here, if no perfect square is easily recognized try dividing by , , or .
Note that the we obtained by simplifying is multiplied, not added, to the already outside the radical.