Which shows the correct simplification of [tex]7^8 \cdot 7^{-4}[/tex]?

A. [tex]7^8 \cdot 7^{-4} = 7^{8 \cdot (-4)} = 7^{-32}[/tex]
B. [tex]7^8 \cdot 7^{-4} = 7^{8 + (-4)} = 7^{-2}[/tex]
C. [tex]7^8 \cdot 7^{-4} = 7^{8 + (-4)} = 7^4[/tex]
D. [tex]7^8 \cdot 7^{-4} = 7^8 \cdot (-4) = 7^{12}[/tex]



Answer :

Let's explore the multiplication of exponents with the same base to simplify the expression \( 7^8 \cdot 7^{-4} \).

When multiplying exponential expressions that have the same base, you add the exponents. This property can be expressed as:
[tex]\[ a^m \cdot a^n = a^{m+n} \][/tex]

Here, the base \( a \) is 7, \( m \) is 8, and \( n \) is -4.

Following the property, let's add the exponents:

[tex]\[ 7^8 \cdot 7^{-4} = 7^{8 + (-4)} \][/tex]

Perform the addition in the exponent:

[tex]\[ 8 + (-4) = 4 \][/tex]

Therefore, the expression simplifies to:

[tex]\[ 7^8 \cdot 7^{-4} = 7^4 \][/tex]

Among the given options, we find the correct simplification step-by-step:

[tex]\[ 7^8 \cdot 7^{-4}=7^{8+(-4)}=7^4 \][/tex]

Thus, the correct simplification is:
[tex]\[ 7^8 \cdot 7^{-4} = 7^4 \][/tex]

Additionally, let's calculate the final value of \( 7^4 \):

[tex]\[ 7^4 = 7 \times 7 \times 7 \times 7 = 2401 \][/tex]

So, the simplified exponent is \( 4 \) and the simplified result of the expression \( 7^4 \) is \( 2401 \). Overall, the correct answer is:

[tex]\[ 7^8 \cdot 7^{-4}=7^{8+(-4)}=7^4 \][/tex]