Last updated on August 27th, 2025
Simplifying radical expressions in algebra means reducing an expression that contains a square root (or other roots) into the simplest form and removing the radical if possible.
Simplifying radical expressions means reducing expressions by taking out perfect squares (or high powers) from under the root. If any radical is in the denominator, we remove it by multiplying by a suitable expression. For example, the conjugate in the case of a binomial, and the same radical in the case of a monomial.
Let us examine a radical expression simplification example. Consider, f(x)=√(4x2y6). We must find pairs of identical factors 4x2y6 to simplify and break it down: f(x)=√(2 × 2 × x × x × y3 × y3)=√(22 × x2 × (y6))=2 |x| |y3| Here we use absolute values, |x| because square roots are always non-negative.
Reducing expressions with square, cube, or nth roots to their most basic form by eliminating or minimizing the radicals is known as simplifying radical expressions. Let us examine some detailed examples that simplify the expression using common techniques like multiplying by the conjugate or pairing factors under the root.
Let’s look at an example of how to use the square root to simplify radical expressions. Think about the radical √48. Until no more simplification is possible, we will reduce this radical expression to its most basic form.
Step 1: Find the factors of the number under the radical.
48=2 × 2 × 2 × 2 × 3
Step 2: Write the number under the radical as a product of its factors as powers of 2.
48=22 × 22 × 3
Step 3: List the factors outside the radical that have the power of 2.
√48=√(22 × 22 × 3)=2 × 2 × √3
Step 4: Reduce the radical to the point where it can no longer be simplified.
√48=4√3
There is no more perfect square factor left, so the radical expression √48 cannot be further simplified, so it is simplified to 4√3.
Let us look at an example of how radical expressions with cube roots or higher roots can be made simpler. Determine the radical expression 426 × 44× 6 × 3. We will keep simplifying the radical expression step by step until we reach a point where it can’t be simplified any further.
Step 1: Break each number down into powers of prime numbers.
44=(22)4=28
6=2 × 3
3=3
Now, the expression is,
426 × 28× 2 × 3 × 3
Step 2: Put all similar terms together. Combine all the same bases’ power now.
26 × 28 × 2=26+8+1=215
3 × 3=32
Now, the expression is,
4215 × 32
Step 3: Divide into a group of four persons (since it’s a fourth root)
Break down 215 into powers of 4:
215=(24)3× 23=163× 23
Now, keep 32 it as it is (because it’s not divisible by 4).
So,
4215 × 32=4(24)3 × 23 × 32
Now, separate into,
=4(24)3 × 423 × 32
Now simplify as:
4(24)3=23=8
The expression becomes:
8 × 423 × 32=8472
Using variables to simplify radical expressions works the same way as using numbers. Together with the numbers, we factorize the variables. To understand it better, let’s go through an example that uses variables to simplify radical expressions. Examine the radical expression √(105 x2y4z1).
Step 1: Divide 105 into prime factors by factoring the number under the square root
105=3 × 5 × 7
Here, we write it as,
√(3 × 5 × 7 × x2 × y4 × z)
Step 2: Applying the square root to perfect squares,
x2 → perfect square
√x2=x
y4 → perfect square
√y2=y2
Since they are not perfect squares, 3, 5, 7, and z. They cannot be simplified further and stay inside the square root.
Now,
Here we simplify as
xy2√(3 × 5 × 7 × z) = xy2√105z
We now know how to simplify various radical expression types. Let us review some radical expression simplification guidelines that can be applied to more complicated radical expressions. If a and b are real numbers, then we get:
Simplifying radical expressions helps in real-life situations. Let us see how it is useful.
Architecture and Construction
Builders can determine the diagonal of a square room to cut materials by simplifying √(52 + 52)=√50=5√2
Navigation and GPS systems
GPS uses a formula √[(x2−x1)2 + (y2−y1)2] similar to the modulus to calculate the straight-line distance between two locations. It helps find how far one point is from another based on its coordinates.
In physics (velocity calculation)
v=√(2gh) simplified to find the velocity of a falling object, or how quickly it hits the ground.
Finance and statistics
Analysts use the square root of variance to find the standard deviation, which helps them understand how much financial data varies, a key part of measuring risk.
Game development and computer graphics
The simplified formula√[(x2−x1)2 + (y2 −y1)2] is used by game engines to calculate the exact distance between moving objects for fluid animation.
Let us see some common mistakes students make while simplifying radical expressions.
Make √50 simpler
5√2
Here,
√(25 × 2)=√25 × √2=5√2
The factor 50 is simplified into a perfect square (25).
√72 simplify
6√2
Here,
We need to get the perfect square factor for 72.
So, divide 72 by 36 × 2 to get
√(36 × 2)=6√2
√72=√(36 × 2)=√36 × √2=6√2 .
The largest perfect square of 72 is 36. Therefore, √2 remains in the root while 6 appears.
Simplify √(x6)
x3
Here,
√(x6)=√((x3)2)=x3 When simplifying, take half the exponent because x6 it is a perfect square and it is an even exponent.
Simplify √(75x2)
5x√3
Divide 75 by 25 × 3 to get,
√(75x2)=√(25 × 3 × x2)=√25 × √3 × √x2=5x√3
Take the square root of 25, which is 5, and x2 (which is x), and subtract √3 from the result. So, the final result is 5x√3.
Simplify (3√2) + (5√2)
8√2
Add the radicals like coefficients such as,
3√2 + 5√2=8√2.
Just like terms, you can add the coefficients of both terms because they share the same radical part (√2).