7^-3 • 7^-5

Answer 1

To simplify the expression $7^{-3}\cdot 7^{-5}$, you can use the property of exponents that states $a^m\cdot a^n=a^{m+n}$.

Applying this property:

$$7^{-3}\cdot 7^{-5}=7^{-3+(-5)}=7^{-8}$$

So, the simplified result is:

$$7^{-8}$$

If you want to express $7^{-8}$ as a positive exponent, you can write:

$$7^{-8}=\frac{1}{7^8}$$

Thus, the final answer can be written as either $7^{-8}$ or $\frac{1}{7^8}$.