Examples with solutions for Multiplication of Powers: Applying the formula

Exercise #1

Simplify the following equation:

45×45= 4^5\times4^5=

Step-by-Step Solution

To simplify the expression 45×45 4^5 \times 4^5 , we will use the rule of exponents that states when multiplying two powers with the same base, you can add the exponents. This rule can be expressed as:

  • am×an=am+na^m \times a^n = a^{m+n}

In this equation, both terms 45 4^5 have the same base 4 4 .

According to the multiplication of powers rule:

  • 45×45=45+54^5 \times 4^5 = 4^{5+5}

Now, simply add the exponents:

45+5=4104^{5+5} = 4^{10}

The simplified form of 45×45 4^5 \times 4^5 is therefore 410 4^{10} .

Answer

410 4^{10}

Exercise #2

79×71= 7^9\times7^1=

Step-by-Step Solution

To solve the expression 79×71 7^9 \times 7^1 , we need to apply the rules of exponents, specifically the multiplication of powers rule. According to this rule, when we multiply two powers with the same base, we keep the base and add the exponents together.


  • The expression can be written as am×an=am+n a^m \times a^n = a^{m+n} , where a a is the base and m m and n n are the exponents.
  • In this case, our base a a is 7, and our exponents are 9 and 1.
  • Applying the formula, we have: 79×71=79+1 7^9 \times 7^1 = 7^{9+1} .
  • Simplifying the exponent: 9+1=10 9 + 1 = 10 .

Thus, the expression simplifies to: 710 7^{10} .

Answer

710 7^{10}

Exercise #3

42×44= 4^2\times4^4=

Video Solution

Step-by-Step Solution

To solve the exercise we use the property of multiplication of powers with the same bases:

anam=an+m a^n * a^m = a^{n+m}

With the help of this property, we can add the exponents.

42×44=44+2=46 4^2\times4^4=4^{4+2}=4^6

Answer

46 4^6

Exercise #4

828385= 8^2\cdot8^3\cdot8^5=

Video Solution

Step-by-Step Solution

All bases are equal and therefore the exponents can be added together.

828385=810 8^2\cdot8^3\cdot8^5=8^{10}

Answer

810 8^{10}

Exercise #5

2102726= 2^{10}\cdot2^7\cdot2^6=

Video Solution

Step-by-Step Solution

We use the power property to multiply terms with identical bases:

aman=am+n a^m\cdot a^n=a^{m+n} Keep in mind that this property is also valid for several terms in the multiplication and not just for two, for example for the multiplication of three terms with the same base we obtain:

amanak=am+nak=am+n+k a^m\cdot a^n\cdot a^k=a^{m+n}\cdot a^k=a^{m+n+k} When we use the mentioned power property twice, we could also perform the same calculation for four terms of the multiplication of five, etc.,

Let's return to the problem:

Keep in mind that all the terms in the multiplication have the same base, so we will use the previous property:

2102726=210+7+6=223 2^{10}\cdot2^7\cdot2^6=2^{10+7+6}=2^{23} Therefore, the correct answer is option c.

Answer

223 2^{23}

Exercise #6

79×7= 7^9\times7=

Video Solution

Step-by-Step Solution

According to the property of powers, when there are two powers with the same base multiplied together, the exponents should be added.

According to the formula:an×am=an+m a^n\times a^m=a^{n+m}

It is important to remember that a number without a power is equivalent to a number raised to 1, not to 0.

Therefore, if we add the exponents:

79+1=710 7^{9+1}=7^{10}

Answer

710 7^{10}

Exercise #7

Choose the expression that is equal to the following:

a4a5 a^4\cdot a^5

Video Solution

Step-by-Step Solution

We will use the law of exponents:

aman=am+n a^m\cdot a^n=a^{^{m+n}}

which means that when multiplying identical numbers raised to any power (meaning - identical bases raised to not necessarily identical powers), we can keep the same base and add the exponents of the numbers,
let's apply this law to the problem:

a4a5=a4+5=a9 a^4\cdot a^5=a^{4+5}=a^9

Let's note something important, that this solution can also be explained verbally, since raising to a power means multiplying the number (base) by itself as many times as the exponent indicates, and therefore multiplying a a by itself 4 times and multiplying the result by the result of multiplying a a by itself 5 times is like multiplying a a by itself 9 times, meaning multiplication between identical numbers (identical bases) raised to powers, not necessarily identical, can be calculated by keeping the same base (same number) and adding the exponents.

Answer

a9 a^9

Exercise #8

Reduce the following equation:

43×45= 4^3\times4^{-5}=

Step-by-Step Solution

To solve the expression 43×45 4^3 \times 4^{-5} , we need to apply the multiplication of powers rule. This rule states that when you multiply two powers with the same base, you can add their exponents. Mathematically, this is expressed as:

  • am×an=am+n a^m \times a^n = a^{m+n}

In our case, the base a a is 4, and the exponents m m and n n are 3 and -5, respectively.

Applying the rule:

43×45=43+(5) 4^3 \times 4^{-5} = 4^{3 + (-5)}

Simplifying the exponent:

3+(5)=2 3 + (-5) = -2

So, the expression simplifies to:

42 4^{-2}

This is the reduced form of the given equation.

Answer

42 4^{-2}

Exercise #9

54×25= 5^4\times25=

Video Solution

Step-by-Step Solution

To solve this exercise, first we note that 25 is the result of a power and we reduce it to a common base of 5.

25=5 \sqrt{25}=5 25=52 25=5^2 Now, we go back to the initial exercise and solve by adding the powers according to the formula:

an×am=an+m a^n\times a^m=a^{n+m}

54×25=54×52=54+2=56 5^4\times25=5^4\times5^2=5^{4+2}=5^6

Answer

56 5^6

Exercise #10

7x7x=? 7^x\cdot7^{-x}=\text{?}

Video Solution

Step-by-Step Solution

We use the law of exponents to multiply terms with identical bases:

aman=am+n a^m\cdot a^n=a^{m+n} We apply the law to given the problem:

7x7x=7x+(x)=7xx=70 7^x\cdot7^{-x}=7^{x+(-x)}=7^{x-x}=7^0 In the first stage we apply the above power rule and in the following stages we simplify the expression obtained in the exponent,

Subsequently, we use the zero power rule:

X0=1 X^0=1 We obtain:

70=1 7^0=1 Lastly we summarize the solution to the problem.

7x7x=7xx=70=1 7^x\cdot7^{-x}=7^{x-x}=7^0 =1 Therefore, the correct answer is option B.

Answer

1 1

Exercise #11

53505255= 5^{-3}\cdot5^0\cdot5^2\cdot5^5=

Video Solution

Step-by-Step Solution

We use the power property to multiply terms with identical bases:

aman=am+n a^m\cdot a^n=a^{m+n} Keep in mind that this property is also valid for several terms in the multiplication and not just for two, for example for the multiplication of three terms with the same base we obtain:

amanak=am+nak=am+n+k a^m\cdot a^n\cdot a^k=a^{m+n}\cdot a^k=a^{m+n+k} When we use the mentioned power property twice, we could also perform the same calculation for four terms of the multiplication of five, etc.,

Let's return to the problem:

Keep in mind that all the terms of the multiplication have the same base, so we will use the previous property:

53505255=53+0+2+5=54 5^{-3}\cdot5^0\cdot5^2\cdot5^5=5^{-3+0+2+5}=5^4 Therefore, the correct answer is option c.

Note:

Keep in mind that 50=1 5^0=1

Answer

54 5^4

Exercise #12

101021041010= 10\cdot10^2\cdot10^{-4}\cdot10^{10}=

Video Solution

Step-by-Step Solution

We use the power property to multiply terms with identical bases:

aman=am+n a^m\cdot a^n=a^{m+n} Keep in mind that this property is also valid for several terms in the multiplication and not just for two, for example for the multiplication of three terms with the same base we obtain:

amanak=am+nak=am+n+k a^m\cdot a^n\cdot a^k=a^{m+n}\cdot a^k=a^{m+n+k} When we use the mentioned power property twice, we could also perform the same calculation for four terms of the multiplication of five, etc.,

Let's return to the problem:

First keep in mind that:

10=101 10=10^1 Keep in mind that all the terms of the multiplication have the same base, so we will use the previous property:

1011021041010=101+24+10=109 10^1\cdot10^2\cdot10^{-4}\cdot10^{10}=10^{1+2-4+10}=10^9

Therefore, the correct answer is option c.

Answer

109 10^9

Exercise #13

Simplify the following equation:

1110×1111= 11^{10}\times11^{11}=

Video Solution

Answer

a'+b' are correct

Exercise #14

Simplify the following equation:

92×99= 9^2\times9^9=

Video Solution

Answer

911 9^{11}

Exercise #15

Simplify the following equation:

83×86= 8^3\times8^6=

Video Solution

Answer

89 8^9

Exercise #16

Simplify the following equation:

65×67= 6^5\times6^7=

Video Solution

Answer

612 6^{12}

Exercise #17

Simplify the following equation:

32×33= 3^2\times3^3=

Video Solution

Answer

35 3^5

Exercise #18

Solve the following equation:

10×10= 10\times10=

Video Solution

Answer

All answers are correct

Exercise #19

Simplify the following equation:

74×7= 7^4\times7=

Video Solution

Answer

75 7^5

Exercise #20

Simplify the following equation:

5×58= 5\times5^8=

Video Solution

Answer

59 5^9