To subtract \( 4.66 \times 10^{-5} - 7.34 \times 10^{-7} \), we need to express both numbers with the same exponent.
Let's convert \( 4.66 \times 10^{-5} \) to a form with \( 10^{-7} \):
\[ 4.66 \times 10^{-5} = 4.66 \times 10^{-5} \times \frac{100}{100} = 4.66 \times 10^{-5} = 466 \times 10^{-7} \]
Now we can perform the subtraction:
\[ 466 \times 10^{-7} - 7.34 \times 10^{-7} = (466 - 7.34) \times 10^{-7} = 458.66 \times 10^{-7} \]
To express this in scientific notation, we convert \( 458.66 \) back to a number that is between 1 and 10:
\[ 458.66 \times 10^{-7} = 4.5866 \times 10^{-5} \]
So, the result of the subtraction \( 4.66 \times 10^{-5} - 7.34 \times 10^{-7} \) is:
\[ \boxed{4.5866 \times 10^{-5}} \]