Examples with solutions for Multiplication of Powers: Applying the formula

Exercise #1

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 #2

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 #3

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 #4

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 #5

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 #6

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 #7

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 #8

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 #9

Simplify the following equation:

1110×1111= 11^{10}\times11^{11}=

Video Solution

Answer

a'+b' are correct

Exercise #10

Simplify the following equation:

92×99= 9^2\times9^9=

Video Solution

Answer

911 9^{11}

Exercise #11

Simplify the following equation:

83×86= 8^3\times8^6=

Video Solution

Answer

89 8^9

Exercise #12

Simplify the following equation:

65×67= 6^5\times6^7=

Video Solution

Answer

612 6^{12}

Exercise #13

Simplify the following equation:

32×33= 3^2\times3^3=

Video Solution

Answer

35 3^5

Exercise #14

Solve the following equation:

10×10= 10\times10=

Video Solution

Answer

All answers are correct

Exercise #15

Simplify the following equation:

74×7= 7^4\times7=

Video Solution

Answer

75 7^5

Exercise #16

Simplify the following equation:

5×58= 5\times5^8=

Video Solution

Answer

59 5^9

Exercise #17

Simplify the following equation:

152×154= 15^2\times15^4=

Video Solution

Answer

156 15^6

Exercise #18

Simplify the following equation:

105×107×102= 10^5\times10^7\times10^2=

Video Solution

Answer

a'+b' are correct

Exercise #19

Simplify the following equation:

133×134×132= 13^3\times13^4\times13^2=

Video Solution

Answer

139 13^9

Exercise #20

Simplify the following equation:

154×15×153= 15^4\times15\times15^3=

Video Solution

Answer

158 15^8