Radical expressionsRules for simplifying radical expression. Discuss and give example

3 Answers | Add Yours

hala718's profile pic

hala718 | High School Teacher | (Level 1) Educator Emeritus

Posted on

The radical numbers ar numbers written into the form of sqrt(a).

There are rules for simplifying.

Rule (1):

sqrt(a*b) = sqrt(a)* sqrt(b)

sqrt(a/b) = sqrt(a)/sqrt(b)

Example:

sqrt15 = sqrt(3*5) = sqrt3 * sqrt5

sqrt(9/4) = sqrt9/sqrt4 = 3/2

 

Rule (2):

sqrt(a+-b) does NOT equal sqrt(a) +- sqrt(b)

Example:

sqrt(16) = sqrt(8+8) = 4

However, sqrt8 + sqrt8 = 2sqrt2 + 2sqrt2 = 4sqrt2

Then sqrt(8+8) does not equal sqrt8 + sqrt8.

nipun-gupta28's profile pic

nipun-gupta28 | Student, College Freshman | eNotes Newbie

Posted on

A radical expression is an expression containing a square root. here i have simplify radical expression which is mentioned below:

Evaluate the radical expression  when a = 2 and b = 4.
Choices:
A. 9
B. 8 
C. 7
D. 6
Correct Answer: D
Solution:
Step 1: [Substitute the values of a and b in the given radical expression.]
Step 2: [Find the positive square root.]
Step 3: [Multiply.]
Step 4: [Add.]
Step 5: = 6                                            [Simplify.]

 

giorgiana1976's profile pic

giorgiana1976 | College Teacher | (Level 3) Valedictorian

Posted on

One rule is to re-write 2 numbers, that are multiplied under the radical sign, under 2 different square root signs.

For instance:

sqrt[(16)*(25)] = sqrt(16)*sqrt(25)

sqrt(400) = 4*5

20 = 20

Another rule states that 2 radical expressions are multiplied, we can re-write the product of radicands under the same radical sign.

For instance:

sqrt(3)*sqrt(4) = sqrt[(3)*(4)]

sqrt(3)*sqrt(4) = sqrt12

We’ve answered 318,991 questions. We can answer yours, too.

Ask a question