Answered

Discover a wealth of knowledge at Westonci.ca, where experts provide answers to your most pressing questions. Find reliable answers to your questions from a wide community of knowledgeable experts on our user-friendly Q&A platform. Connect with a community of professionals ready to help you find accurate solutions to your questions quickly and efficiently.

Simplify the following expression:

[tex]\[ 7^{-\frac{5}{6}} \cdot 7^{-\frac{7}{6}} \][/tex]

A. [tex]\(\frac{1}{14}\)[/tex]

B. 14

C. 49

D. [tex]\(\frac{1}{49}\)[/tex]


Sagot :

To simplify the expression [tex]\( 7^{-\frac{5}{6}} \cdot 7^{-\frac{7}{6}} \)[/tex], we can use the properties of exponents. Specifically, we use the property that states:

[tex]\[ a^m \cdot a^n = a^{m+n} \][/tex]

Here, our base [tex]\( a \)[/tex] is 7, and the exponents are [tex]\(-\frac{5}{6}\)[/tex] and [tex]\(-\frac{7}{6}\)[/tex]. We add these exponents together to combine them into a single exponent:

[tex]\[ -\frac{5}{6} + -\frac{7}{6} = -\left(\frac{5}{6} + \frac{7}{6}\right) = -\frac{5 + 7}{6} = -\frac{12}{6} = -2 \][/tex]

This means:

[tex]\[ 7^{-\frac{5}{6}} \cdot 7^{-\frac{7}{6}} = 7^{-2} \][/tex]

Next, we simplify [tex]\( 7^{-2} \)[/tex]. The property of negative exponents states:

[tex]\[ a^{-m} = \frac{1}{a^m} \][/tex]

Using this property, we get:

[tex]\[ 7^{-2} = \frac{1}{7^2} \][/tex]

We know that [tex]\( 7^2 = 49 \)[/tex], so:

[tex]\[ 7^{-2} = \frac{1}{49} \][/tex]

Therefore, the simplified expression is:

[tex]\[ \boxed{\frac{1}{49}} \][/tex]