Precalculus Examples

$\log (20) + \log (20 - 15)$

Step 1

Use the product property of logarithms, $\log_{b} (x) + \log_{b} (y) = \log_{b} (x y)$ .

$\log (20 (20 - 15))$

Step 2

Subtract $15$ from $20$ .

$\log (20 \cdot 5)$

Step 3

Multiply $20$ by $5$ .

$\log (100)$

Step 4

Logarithm base $10$ of $100$ is $2$ .

$2$