Math Fundamentals18 sections · 814 units
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Quotient Rule (Division becomes subtraction)

Second logarithm property

When you divide two numbers inside a logarithm, you can split it into a difference: logb(xy)=logb(x)logb(y)\log_b\left(\frac{x}{y}\right) = \log_b(x) - \log_b(y).

For example, log2(324)=log2(32)log2(4)=52=3\log_2\left(\frac{32}{4}\right) = \log_2(32) - \log_2(4) = 5 - 2 = 3. And indeed, log2(8)=3\log_2(8) = 3.

This turns division into subtraction. Combined with the product rule, you can break down complex expressions into simpler pieces.