Get the information you need quickly and easily with IDNLearn.com. Get accurate and detailed answers to your questions from our dedicated community members who are always ready to help.

Simplify the expression:
[tex]\[ \sqrt{45w} - \sqrt{20w} \][/tex]

Assume that the variable [tex]\( w \)[/tex] represents a positive real number.


Sagot :

Certainly! Let's solve the expression step by step.

Given:

[tex]\[ \sqrt{45w} - \sqrt{20w} \][/tex]

First, we simplify each square root term individually.

Starting with [tex]\(\sqrt{45w}\)[/tex]:

1. Factor 45 into its prime factors:
[tex]\[ 45 = 9 \times 5 = 3^2 \times 5 \][/tex]
2. Rewrite the expression:
[tex]\[ \sqrt{45w} = \sqrt{(3^2 \times 5 \times w)} \][/tex]
3. Using the property of square roots that [tex]\(\sqrt{a \times b} = \sqrt{a} \times \sqrt{b}\)[/tex], we can simplify:
[tex]\[ \sqrt{(3^2 \times 5 \times w)} = \sqrt{3^2} \times \sqrt{5} \times \sqrt{w} = 3 \times \sqrt{5} \times \sqrt{w} \][/tex]
Thus:
[tex]\[ \sqrt{45w} = 3 \sqrt{5} \sqrt{w} \][/tex]

Next, we simplify [tex]\(\sqrt{20w}\)[/tex]:

1. Factor 20 into its prime factors:
[tex]\[ 20 = 4 \times 5 = 2^2 \times 5 \][/tex]
2. Rewrite the expression:
[tex]\[ \sqrt{20w} = \sqrt{(2^2 \times 5 \times w)} \][/tex]
3. Using the property of square roots:
[tex]\[ \sqrt{(2^2 \times 5 \times w)} = \sqrt{2^2} \times \sqrt{5} \times \sqrt{w} = 2 \times \sqrt{5} \times \sqrt{w} \][/tex]
Thus:
[tex]\[ \sqrt{20w} = 2 \sqrt{5} \sqrt{w} \][/tex]

Now, subtract the simplified terms:

[tex]\[ \sqrt{45w} - \sqrt{20w} = 3 \sqrt{5} \sqrt{w} - 2 \sqrt{5} \sqrt{w} \][/tex]

Both terms have a common factor of [tex]\(\sqrt{5} \sqrt{w}\)[/tex]. Factor this common element out:

[tex]\[ \sqrt{5} \sqrt{w} (3 - 2) = \sqrt{5} \sqrt{w} \times 1 = \sqrt{5} \sqrt{w} \][/tex]

Therefore:

[tex]\[ \sqrt{45w} - \sqrt{20w} = \sqrt{5w} \][/tex]