### Home > CCA2 > Chapter 7 > Lesson 7.1.3 > Problem7-39

7-39.

Homework Help ✎Given that $\log 2 ≈ 0.3010$, $\log 3 ≈ 0.4771$ and $\log 5 ≈ 0.6990$, calculate each of the following logarithms without using a calculator.

1. $\log6$

$\log 6 = \log \left(2⋅3\right)$
Now use the properties of logs to expand.

$\log2 + \log3 ≈ 0.7781$

1. $\log15$

Express 15 as a product of numbers whose logs are given.

See part (a).

1. $\log9$

$\log 9$ can be rewritten as $\log\left(3 · 3\right)$ or $\log 3^{2}$. Try both.

1. $\log50$

$50 = 2 · 5^{2}$