Fully simplify and write your answer in exponential form with positive exponents only. Example: 153\frac{1}{5^3}

To simplify \( y^{-2} \cdot y^{-6} \), we can use the property of exponents that states when you multiply two powers with the same base, you add the exponents:

\[
y^{-2} \cdot y^{-6} = y^{-2 + (-6)} = y^{-8}
\]

Now, to express this in exponential form with positive exponents only, we can rewrite \( y^{-8} \) using the property that \( a^{-n} = \frac{1}{a^n} \):

\[
y^{-8} = \frac{1}{y^8}
\]

Thus, the fully simplified expression is:

\[
\frac{1}{y^8}
\]