Math Fundamentals18 sections · 814 units
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Product Rule (Multiplication becomes addition)

First logarithm property

When you multiply two numbers inside a logarithm, you can split it into a sum: log⁡b(xy)=log⁡b(x)+log⁡b(y)\log_b(xy) = \log_b(x) + \log_b(y).

For example, log⁡2(8×4)=log⁡2(8)+log⁡2(4)=3+2=5\log_2(8 \times 4) = \log_2(8) + \log_2(4) = 3 + 2 = 5. And indeed, log⁡2(32)=5\log_2(32) = 5.

This property turns multiplication into addition, which makes calculations easier. You'll use this when analyzing nested loops or recursive algorithms that split problems into multiple parts.