Exponents and Roots

What is an exponent?

An exponent tells us the amount of times a number is to be multiplied by itself.

What is a root?

A root is the inverse operation of exponentiation, which helps us discover which number multiplied by itself gives this result.

The square root is equal to the power of 0.5.

Exponents and the Base of the Exponents

Practice Powers and Roots - Basic

Examples with solutions for Powers and Roots - Basic

Exercise #1

Choose the expression that is equal to the following:

27 2^7

Video Solution

Step-by-Step Solution

To solve this problem, we'll focus on expressing the power 27 2^7 as a series of multiplications.

  • Step 1: Identify the given power expression 27 2^7 .
  • Step 2: Convert 27 2^7 into a product of repeated multiplication. This involves writing 2 multiplied by itself for a total of 7 times.
  • Step 3: The expanded form of 27 2^7 is 2×2×2×2×2×2×2 2 \times 2 \times 2 \times 2 \times 2 \times 2 \times 2 .

By comparing this expanded form with the provided choices, we see that the correct expression is:

2222222 2\cdot2\cdot2\cdot2\cdot2\cdot2\cdot2

Therefore, the solution to the problem is the expression that matches this expanded multiplication form, which is the choice 1: 2222222\text{1: } 2\cdot2\cdot2\cdot2\cdot2\cdot2\cdot2.

Answer

2222222 2\cdot2\cdot2\cdot2\cdot2\cdot2\cdot2

Exercise #2

Which of the following is equivalent to the expression below?

10,0001 10,000^1

Video Solution

Step-by-Step Solution

To solve this problem, we will apply the rule of exponents:

  • Any number raised to the power of 1 remains unchanged. Therefore, by the identity property of exponents, 10,0001=10,000 10,000^1 = 10,000 .

Given the choices:

  • 10,00010,000 10,000 \cdot 10,000 : This is 10,0002 10,000^2 .
  • 10,0001 10,000 \cdot 1 : Simplifying this expression yields 10,000, which is equivalent to 10,0001 10,000^1 .
  • 10,000+10,000 10,000 + 10,000 : This results in 20,000, not equivalent to 10,0001 10,000^1 .
  • 10,00010,000 10,000 - 10,000 : This results in 0, not equivalent to 10,0001 10,000^1 .

Therefore, the correct choice is 10,0001 10,000 \cdot 1 , which simplifies to 10,000, making it equivalent to 10,0001 10,000^1 .

Thus, the expression 10,0001 10,000^1 is equivalent to:

10,0001 10,000 \cdot 1

Answer

10,0001 10,000\cdot1

Exercise #3

4= \sqrt{4}=

Video Solution

Step-by-Step Solution

To solve this problem, we'll determine the square root of the number 4.

  • Step 1: Recognize that the square root of a number is asking for a value that, when multiplied by itself, yields the original number. Here, we seek a number yy such that y2=4y^2 = 4.
  • Step 2: Identify that 44 is a perfect square. The numbers 22 and 2-2 both satisfy the equation 22=42^2 = 4 and (2)2=4(-2)^2 = 4.
  • Step 3: We usually consider the principal square root, which is the non-negative version. Thus, 4=2\sqrt{4} = 2.

Therefore, the solution to the problem is 2, which corresponds to the correct choice from the given options.

Answer

2

Exercise #4

9= \sqrt{9}=

Video Solution

Step-by-Step Solution

To solve this problem, we want to find the square root of 9.

Step 1: Recognize that a square root is a number which, when multiplied by itself, equals the original number. Thus, we are seeking a number x x such that x2=9 x^2 = 9 .

Step 2: Note that 9 is a common perfect square: 9=3×3 9 = 3 \times 3 . Therefore, the square root of 9 is the number that, when multiplied by itself, gives 9. This number is 3.

Step 3: Since we are interested in the principal square root, we consider only the non-negative value. Hence, the principal square root of 9 is 3.

Therefore, the solution to the problem is 3 3 .

Answer

3

Exercise #5

16= \sqrt{16}=

Video Solution

Step-by-Step Solution

To determine the square root of 16, follow these steps:

  • Identify that we are looking for the square root of 16, which is a number that, when multiplied by itself, equals 16.
  • Recall the basic property of perfect squares: 4×4=16 4 \times 4 = 16 .
  • Thus, the square root of 16 is 4.

Hence, the solution to the problem is the principal square root, which is 4 4 .

Answer

4

Exercise #6

36= \sqrt{36}=

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Understand the definition of a square root.
  • Step 2: Identify which integer, when squared, gives 36.
  • Step 3: Verify this integer meets the required condition.
  • Step 4: Choose the correct answer from the given choices.

Now, let's work through each step:
Step 1: A square root of a number is a value that, when multiplied by itself, gives the original number. Here, we want y y such that y2=36 y^2 = 36 .
Step 2: We test integer values to find which one squared equals 36. Testing y=1,2,3,4,5, y = 1, 2, 3, 4, 5, and 6 6 gives:
- 12=1 1^2 = 1
- 22=4 2^2 = 4
- 32=9 3^2 = 9
- 42=16 4^2 = 16
- 52=25 5^2 = 25
- 62=36 6^2 = 36

Step 3: The integer 6 6 satisfies 62=36 6^2 = 36 . Therefore, 36=6 \sqrt{36} = 6 .

Step 4: The correct choice from the given answer choices is 6 (Choice 4).

Hence, the square root of 36 is 6 \mathbf{6} .

Answer

6

Exercise #7

49= \sqrt{49}=

Video Solution

Step-by-Step Solution

To solve this problem, we follow these steps:

  • Step 1: Understand that finding the square root of a number means determining what number, when multiplied by itself, equals the original number.
  • Step 2: Identify the numbers that could potentially be the square root of 4949. These are ±7 \pm7, but by convention, the square root function typically refers to the non-negative root.
  • Step 3: Calculate 7×7=497 \times 7 = 49. This confirms that 49=7 \sqrt{49} = 7.
  • Step 4: Verify using the problem's multiple-choice answers to ensure 77 is among them, confirming choice number .

Therefore, the solution to the problem 49 \sqrt{49} is 7 7 .

Answer

7

Exercise #8

64= \sqrt{64}=

Video Solution

Step-by-Step Solution

To solve this problem, we'll determine the square root of 64, following these steps:

  • Step 1: Identify the number whose square root we need to find. The number given is 64.
  • Step 2: Determine which number, when multiplied by itself, equals 64.
  • Step 3: Recall that 8×8=64 8 \times 8 = 64 .

Now, let's work through each step:

Step 1: We are tasked with finding 64 \sqrt{64} . The problem involves identifying the number which, when squared, results in 64.
Step 2: To find this number, we'll check our knowledge of squares. We know that 8 is a significant integer whose square results in 64.
Step 3: Compute: 8×8=64 8 \times 8 = 64 . Hence, 8 8 meets the requirement.

We find that the solution to the problem is 64=8 \sqrt{64} = 8 .

Answer

8

Exercise #9

81= \sqrt{81}=

Video Solution

Step-by-Step Solution

To solve this problem, follow these steps:

  • Step 1: Understand that the square root of a number n n is a value that, when multiplied by itself, equals n n .
  • Step 2: Identify the number whose square is 81. Since 9×9=81 9 \times 9 = 81 , the square root of 81 is 9.

Therefore, the square root of 81 is 9 9 .

Answer

9

Exercise #10

100= \sqrt{100}=

Video Solution

Step-by-Step Solution

The task is to find the square root of the number 100. The square root operation seeks a number which, when squared, equals the original number. For any positive integer, if x2=100 x^2 = 100 , then x x should be our answer.

Step 1: Recognize that 100 is a perfect square. This means there exists an integer x x such that x×x=100 x \times x = 100 . Generally, we recall basic squares such as:

  • 12=1 1^2 = 1
  • 22=4 2^2 = 4
  • 32=9 3^2 = 9
  • and so forth, up to 102 10^2

Step 2: Checking integers, we find that:

102=10×10=100 10^2 = 10 \times 10 = 100

Step 3: Confirm the result: Since 10×10=100 10 \times 10 = 100 , then 100=10 \sqrt{100} = 10 .

Step 4: Compare with answer choices. Given that one of the choices is 10, and 100=10 \sqrt{100} = 10 , choice 1 is correct.

Therefore, the square root of 100 is 10.

Answer

10

Exercise #11

25= \sqrt{25}=

Video Solution

Step-by-Step Solution

To solve this problem, we need to determine the square root of 25.

  • Step 1: The square root operation asks us to find a number that, when multiplied by itself, equals the given number, 25.
  • Step 2: Consider what number times itself equals 25. We note that 5×5=255 \times 5 = 25.
  • Step 3: Thus, the square root of 25 is 5.

Therefore, the solution to the problem is 25=5\sqrt{25} = 5.

The correct answer is choice 2: 5.

Answer

5

Exercise #12

62= 6^2=

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Recognize that 62 6^2 means 6×6 6 \times 6 .
  • Step 2: Perform the multiplication of 6 by itself.

Now, let's work through each step:
Step 1: The expression 62 6^2 indicates we need to multiply 6 by itself.
Step 2: Calculating 6×6 6 \times 6 gives us 36.

Therefore, the value of 62 6^2 is 36.

Answer

36

Exercise #13

112= 11^2=

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Set up the multiplication as 11×11 11 \times 11 .
  • Step 2: Compute the product using basic arithmetic.
  • Step 3: Compare the result with the provided multiple-choice answers to identify the correct one.

Now, let's work through each step:
Step 1: We begin with the calculation 11×11 11 \times 11 .
Step 2: Perform the multiplication:

  1. Multiply the units digits: 1×1=1 1 \times 1 = 1 .
  2. Next, for the tens digits: 11×10=110 11 \times 10 = 110 .
  3. Add the results: 110+1=111 110 + 1 = 111 . This doesn't seem right, so let's break it down further.

Let's examine a more structured multiplication method:

Multiply 11 11 by 1 1 (last digit of the second 11), we get 11.
Multiply 11 11 by 10 10 (tens place of the second 11), we get 110.

If we align correctly and add the partial products:

     11
+   110
------------
   121

Step 3: The correct multiplication yields the final result as 121 121 . Upon reviewing the provided choices, the correct answer is choice 4: 121 121 .

Therefore, the solution to the problem is 121 121 .

Answer

121

Exercise #14

36= \sqrt{36}=

Video Solution

Step-by-Step Solution

Let's solve the problem step by step:

  • Step 1: Understand what the square root means.
  • The square root of a number nn is a value that, when multiplied by itself, equals nn. This is written as x=nx = \sqrt{n}.

  • Step 2: Apply this definition to the number 3636.
  • We are looking for a number xx such that x2=36x^2 = 36. This translates to finding x=36x = \sqrt{36}.

  • Step 3: Determine the correct number.
  • We know that 6×6=366 \times 6 = 36. Therefore, the principal square root of 3636 is 66.

Thus, the solution to the problem is 36=6 \sqrt{36} = 6 .

Among the given choices, the correct one is: Choice 1: 66.

Answer

6

Exercise #15

64= \sqrt{64}=

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Recognize what finding a square root means
  • Step 2: List known perfect squares to identify which one results in 64
  • Step 3: Verify the square root by calculation

Now, let's work through each step:
Step 1: To find the square root of 64, we seek a number that, when multiplied by itself, equals 64.
Step 2: Consider the sequence of perfect squares: 12=1 1^2 = 1 , 22=4 2^2 = 4 , 32=9 3^2 = 9 , 42=16 4^2 = 16 , 52=25 5^2 = 25 , 62=36 6^2 = 36 , 72=49 7^2 = 49 , 82=64 8^2 = 64 .
Step 3: We see that 82=64 8^2 = 64 . Therefore, the square root of 64 is 8.

Therefore, the solution to this problem is 8 8 .

Answer

8