Question

How do you evaluate $\log 20+\log 50$?

Answer 1

Calculate the value of $\log 20+\log 50$

using the identity

$\log mn=\log m+\log n$ and $\log m^n=n\times \log m$

Now evaluate the given expression using the identity

$$\begin{gathered} \log 20+\log 50=\log (20\times 50) \\ \log 20+\log 50=\log \left(1000\right) \\ \log 20+\log 50=\log \left({10}^3\right) \\ \log 20+\log 50=3\times \log 10 \\ \log 20+\log 50=3 \end{gathered}$$

Hence, the value of $\log 20+\log 50$ is $3$