Examples with solutions for Product Property of Square Roots: Using variables

Exercise #1

Solve the following exercise:

x4= \sqrt{x^4}=

Video Solution

Step-by-Step Solution

In order to simplify the given expression, we will use the following three laws of exponents:

a. The definition of root as an exponent:

an=a1n \sqrt[n]{a}=a^{\frac{1}{n}}

b. Law of exponents for power to a power:

(am)n=amn (a^m)^n=a^{m\cdot n}

Let's start with converting the square root to an exponent using the law of exponents mentioned in a:

x4=(x4)12= \sqrt{x^4}= \\ \downarrow\\ (x^4)^{\frac{1}{2}}= Let's continue, using the law of exponents mentioned in b to perform the exponentiation of the term in parentheses:

(x4)12=x412=x2 (x^4)^{{\frac{1}{2}}} = \\ x^{4\cdot\frac{1}{2}}=\\ \boxed{x^2} Therefore, the correct answer is answer b.

Answer

x2 x^2

Exercise #2

Solve the following exercise:

9x= \sqrt{9x}=

Video Solution

Step-by-Step Solution

In order to simplify the given expression, we will use two laws of exponents:

A. Definition of the root as an exponent:

an=a1n \sqrt[n]{a}=a^{\frac{1}{n}}

B. Law of exponents for dividing powers with the same base:

(ab)n=anbn (a\cdot b)^n=a^n\cdot b^n

Let's start with converting the root to an exponent using the law of exponents shown in A:

9x=(9x)12= \sqrt{9x}= \\ \downarrow\\ (9x)^{\frac{1}{2}}= Next, we will use the law of exponents shown in B and apply the exponent to each of the factors in the numerator that are in parentheses:

(9x)12=912x12=9x=3x (9x)^{\frac{1}{2}}= \\ 9^{\frac{1}{2}}\cdot x^{{\frac{1}{2}}}=\\ \sqrt{9}\sqrt{x}=\\ \boxed{3\sqrt{x}} In the last steps, we will multiply the half exponent by each of the factors in the numerator, returning to the root form, that is, according to the definition of the root as an exponent shown in A (in the opposite direction) and then we will calculate the known fourth root result of the number 9.

Therefore, the correct answer is answer D.

Answer

3x 3\sqrt{x}

Exercise #3

Given the rectangle ABCD

AB=X

The ratio between AB and BC is x2 \sqrt{\frac{x}{2}}

We mark the length of the diagonal A the rectangle in m

Check the correct argument:

XXXmmmAAABBBCCCDDD

Video Solution

Step-by-Step Solution

Given that:

ABBC=x2 \frac{AB}{BC}=\sqrt{\frac{x}{2}}

Given that AB equals X

We will substitute accordingly in the formula:

xBC=x2 \frac{x}{BC}=\frac{\sqrt{x}}{\sqrt{2}}

x2=BCx x\sqrt{2}=BC\sqrt{x}

x2x=BC \frac{x\sqrt{2}}{\sqrt{x}}=BC

x×x×2x=BC \frac{\sqrt{x}\times\sqrt{x}\times\sqrt{2}}{\sqrt{x}}=BC

x×2=BC \sqrt{x}\times\sqrt{2}=BC

Now let's focus on triangle ABC and use the Pythagorean theorem:

AB2+BC2=AC2 AB^2+BC^2=AC^2

Let's substitute the known values:

x2+(x×2)2=m2 x^2+(\sqrt{x}\times\sqrt{2})^2=m^2

x2+x×2=m2 x^2+x\times2=m^2

We'll add 1 to both sides:

x2+2x+1=m2+1 x^2+2x+1=m^2+1

(x+1)2=m2+1 (x+1)^2=m^2+1

Answer

m2+1=(x+1)2 m^2+1=(x+1)^2

Exercise #4

Solve the following exercise:

25x4= \sqrt{25x^4}=

Video Solution

Answer

5x2 5x^2

Exercise #5

Solve the following exercise:

100x2= \sqrt{100x^2}=

Video Solution

Answer

10x 10x

Exercise #6

Solve the following exercise:

49x2= \sqrt{49x^2}=

Video Solution

Answer

7x 7x

Exercise #7

Solve the following exercise:

16x2= \sqrt{16x^2}=

Video Solution

Answer

4x 4x

Exercise #8

Solve the following exercise:

36x= \sqrt{36x}=

Video Solution

Answer

6x 6\sqrt{x}

Exercise #9

Solve the following exercise:

25x2= \sqrt{25x^2}=

Video Solution

Answer

5x 5x

Exercise #10

Solve the following exercise:

5x4= \sqrt{5x^4}=

Video Solution

Answer

5x2 \sqrt{5}x^2

Exercise #11

Solve the following exercise:

36x4= \sqrt{36x^4}=

Video Solution

Answer

6x2 6x^2

Exercise #12

Solve the following exercise:

25x4= \sqrt{25x^4}=

Video Solution

Answer

5x2 5x^2

Exercise #13

Solve the following exercise:

4x4= \sqrt{4x^4}=

Video Solution

Answer

2x2 2x^2

Exercise #14

Solve the following exercise:

12x4= \sqrt{12x^4}=

Video Solution

Answer

12x2 \sqrt{12}x^2

Exercise #15

Solve the following system of equations:

{xy=616xy=9 \begin{cases} \sqrt{x}-\sqrt{y}=\sqrt{\sqrt{61}-6} \\ xy=9 \end{cases}

Video Solution

Answer

x=6122.5 x=\frac{\sqrt{61}}{2}-2.5

y=612+2.5 y=\frac{\sqrt{61}}{2}+2.5

or

x=612+2.5 x=\frac{\sqrt{61}}{2}+2.5

y=6122.5 y=\frac{\sqrt{61}}{2}-2.5

Exercise #16

Solve the following system of equations:

{x+y=61+6xy=9 \begin{cases} \sqrt{x}+\sqrt{y}=\sqrt{\sqrt{61}+6} \\ xy=9 \end{cases}

Video Solution

Answer

x=6122.5 x=\frac{\sqrt{61}}{2}-2.5

y=612+2.5 y=\frac{\sqrt{61}}{2}+2.5

or

x=612+2.5 x=\frac{\sqrt{61}}{2}+2.5

y=6122.5 y=\frac{\sqrt{61}}{2}-2.5