Math Fundamentals18 sections · 814 units
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Power Rule (Exponent comes out front)

Third logarithm property

When you take the logarithm of a power, the exponent moves out front as a multiplier: logb(xk)=klogb(x)\log_b(x^k) = k \cdot \log_b(x).

For example, log2(82)=2log2(8)=23=6\log_2(8^2) = 2 \cdot \log_2(8) = 2 \cdot 3 = 6. And indeed, log2(64)=6\log_2(64) = 6.

This is the most powerful property for complexity analysis. When you have log(n2)\log(n^2), you can simplify it to 2logn2 \log n, which is still O(logn)O(\log n) because the constant 22 drops in Big-O notation.