Examples with solutions for Powers and Roots: Solving an exercise

Exercise #1

Solve the following exercise and circle the correct answer:

4243= 4^2-4^3=

Video Solution

Step-by-Step Solution

To solve the expression 4243 4^2 - 4^3 , we start by evaluating each power separately:

  • Calculate 42 4^2 :
    42 4^2 means 4 4 multiplied by itself, which is 4×4=16 4 \times 4 = 16 .

  • Calculate43 4^3 :
    43 4^3 means 4 4 multiplied by itself three times, which is 4×4×4=64 4 \times 4 \times 4 = 64 .

Next, substitute these values back into the expression:

  • 4243=1664 4^2 - 4^3 = 16 - 64

Perform the subtraction:

  • 1664=48 16 - 64 = -48

Thus, the correct answer is 48-48.

Answer

-48

Exercise #2

Solve the following exercise and circle the correct answer:

7172= 7^1-7^2=

Video Solution

Step-by-Step Solution

To solve the expression 7172 7^1 - 7^2 , we need to evaluate the powers first before performing the subtraction. The steps are as follows:

  • Calculate 71 7^1 : Since any number to the power of 1 is the number itself, we have 71=7 7^1 = 7 .
  • Calculate 72 7^2 : This means 7 is multiplied by itself, which gives us 7×7=49 7 \times 7 = 49 .
  • Subtract the results: Now, perform the subtraction 749 7 - 49 .
  • This yields: 749=42 7 - 49 = -42 .

Thus, the correct answer is 42 -42 .

Answer

42 -42

Exercise #3

Solve the following exercise and circle the correct answer:

6362= 6^3-6^2=

Video Solution

Step-by-Step Solution

To solve the expression 6362 6^3 - 6^2 , we will follow the order of operations, which in this case involves evaluating the powers before the subtraction operation.

  • First, evaluate 63 6^3 :
    • 63 6^3 means 6×6×6 6 \times 6 \times 6 .
    • Calculating this, we get 6×6=36 6 \times 6 = 36 .
    • Then multiply 36 by 6 to get 36×6=216 36 \times 6 = 216 .
  • Next, evaluate 62 6^2 :
    • 62 6^2 means 6×6 6 \times 6 .
    • Calculating this gives us 36 36 .
  • Finally, subtract the second result from the first:
    • That is 21636 216 - 36 .
    • Performing the subtraction, we get 180 180 .

Thus, the result of the expression 6362 6^3 - 6^2 is 180 180 .

Answer

180

Exercise #4

Solve the following exercise and circle the correct answer:

5241= 5^2-4^1=

Video Solution

Step-by-Step Solution

To solve the exercise 5241= 5^2-4^1= , we need to follow the order of operations, specifically focusing on powers (exponents) before performing subtraction.

  • Step 1: Calculate 52 5^2 . This means we multiply 5 by itself: 5×5=25 5 \times 5 = 25 .

  • Step 2: Calculate 41 4^1 . Any number to the power of 1 is itself, so 41=4 4^1 = 4 .

  • Step 3: Subtract the result of 41 4^1 from 52 5^2 : 254 25 - 4 .

  • Step 4: Complete the subtraction: 254=21 25 - 4 = 21 .

Thus, the correct answer is 21 21 .

Answer

21

Exercise #5

Solve the following question:

244:22= 2^4-4:2^2=

Video Solution

Step-by-Step Solution

To solve the expression 244:22 2^4-4:2^2 , we must follow the order of operations, also known as BIDMAS/BODMAS (Brackets, Indices/Orders, Division/Multiplication, Addition/Subtraction).

1. 1. Start with calculating the powers (indices) in the expression:

  • 24=16 2^4 = 16
  • 22=4 2^2 = 4

2. 2. Substitute these values back into the expression:

164:4 16 - 4 : 4

3. 3. Next, perform the division:

4:4=1 4 : 4 = 1

4. 4. Substitute back again and perform the final subtraction:

161=15 16 - 1 = 15

Therefore, the solution to the expression 244:22 2^4-4:2^2 is 15.

Answer

15

Exercise #6

Solve the following exercise:

42:2+52= 4^2:2+5^2=

Video Solution

Step-by-Step Solution

To solve the expression 42:2+52 4^2:2+5^2 , we need to follow the order of operations, which is often remembered by the acronym PEMDAS (Parentheses, Exponents, Multiplication and Division, Addition and Subtraction). This guide will help us apply the correct sequence to solve the problem.


  • Step 1: Exponents
    First, we solve the exponents in the expression. In this case, we have 42 4^2 and 52 5^2 .
    Calculate each:
    42=4×4=16 4^2 = 4 \times 4 = 16
    52=5×5=25 5^2 = 5 \times 5 = 25

  • Step 2: Division
    Next, we perform the division operation. In the expression 16:2 16 : 2 , divide 16 by 2:
    16:2=8 16 : 2 = 8

  • Step 3: Addition
    Finally, we add the results from the previous steps together:
    8+25=33 8 + 25 = 33


Thus, the value of the expression 42:2+52 4^2:2+5^2 is 33 33 .

Answer

33

Exercise #7

Solve the following exercise and circle the correct answer:

5242+22= 5^2-4^2+2^2=

Video Solution

Step-by-Step Solution

To solve the expression 5242+22 5^2 - 4^2 + 2^2 , we'll need to follow the order of operations, often remembered by the acronym PEMDAS (Parentheses, Exponents, Multiplication and Division (from left to right), Addition and Subtraction (from left to right)). Here, we only have exponents and basic arithmetic.


  • First, calculate the powers:
    52=25 5^2 = 25 ,
    42=16 4^2 = 16 ,
    22=4 2^2 = 4 .

  • Now substitute the calculated values back into the expression:
    2516+4 25 - 16 + 4 .

  • Perform the subtraction and addition from left to right:
    2516=9 25 - 16 = 9 .

  • Then add 4 to 9:
    9+4=13 9 + 4 = 13 .

The final answer is 13 13 .

Answer

13

Exercise #8

Solve the following question:

3(52:5)2+72= 3-(5^2:5)^2+7^2=

Video Solution

Step-by-Step Solution

To solve the expression 3(52:5)2+72 3-(5^2:5)^2+7^2 , we should follow the order of operations, which is often remembered by the acronym PEMDAS (Parentheses, Exponents, Multiplication and Division (from left to right), Addition and Subtraction (from left to right)).

Here are the steps to solve the expression:

1. Evaluate the exponents

  • Calculate 525^2 which equals 2525.

  • Calculate 727^2 which equals 4949.


2. Evaluate expressions inside parentheses

  • The expression inside the parentheses is 52:55^2:5 which simplifies to 25:5=525:5 = 5.


3. Evaluate the expression inside the parentheses raised to a power

  • The simplified expression now is (5)2(5)^2, which is 2525.


4. Substitute back into the expression

  • The original expression now becomes: 325+493 - 25 + 49.


5. Perform the addition and subtraction from left to right

  • First, calculate 3253 - 25 which equals 22-22.

  • Then, 22+49-22 + 49 equals 2727.


Therefore, the final result of the expression 3(52:5)2+72 3-(5^2:5)^2+7^2 is 2727.

Answer

27

Exercise #9

Solve the following question:

(42:8):2+32= (4^2:8):2+3^2=

Video Solution

Step-by-Step Solution

Let's walk through the steps to solve the expression (42:8):2+32 (4^2:8):2+3^2 using the correct order of operations, often remembered by the acronym PEMDAS (Parentheses, Exponents, Multiplication and Division (from left to right), Addition and Subtraction (from left to right)).

  • First, resolve the expression inside the parentheses: 42:84^2:8

    • The exponent comes first:

      42=164^2 = 16, so the expression now is 16:816:8.

  • Next, perform the division inside the parentheses: 16:816:8 equals 2. So the expression within the parentheses simplifies to 2.

  • Now, we replace the original expression with this simplified result:

    2:2+322:2+3^2

  • We perform the division: 2:2=12:2 = 1.

  • Substitute back into the expression:

    1+321+3^2

  • Next, calculate the exponent:

    32=93^2 = 9.

  • Finally, add the results:

    1+9=101 + 9 = 10.

Thus, the solution to the expression (42:8):2+32 (4^2:8):2+3^2 is 10.

Answer

10

Exercise #10

Solve the following question:

(1810)2+33= (18-10)^2+3^3=

Video Solution

Step-by-Step Solution

To solve the expression (1810)2+33 (18-10)^2+3^3 , we need to follow the order of operations, often remembered by the acronym PEMDAS (Parentheses, Exponents, Multiplication and Division, Addition and Subtraction).

  • Step 1: Parentheses
    First, solve the expression inside the parentheses: 1810 18-10 .
    1810=8 18-10 = 8

  • Step 2: Exponents
    Next, apply the exponents to the numbers:
    (8)2 (8)^2 and 33 3^3 .
    82=64 8^2 = 64
    33=27 3^3 = 27

  • Step 3: Addition
    Finally, add the results of the exponentiations:
    64+27 64 + 27
    64+27=91 64 + 27 = 91

Thus, the final answer is 91 91 .

Answer

91