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Power, Zero, and Negative Index Laws

▸ Power of a Power Law — When raising a power to another power, multiply the indices. Example: (a^m)^n = a^(m*n). For example, (3^2)^4 = 3^(2*4) = 3^8. ▸ Zero Index Law — Any non-zero number raised to the power of zero equals 1. Example: a^0 = 1 (where a ≠ 0). For example, 15^0 = 1. ▸ Negative Index Law — A negative index means the reciprocal of the positive index. Example: a^(-n) = 1 / a^n (where a ≠ 0). For example, 2^(-4) = 1 / 2^4 = 1/16. ★ Real-world — Medicine Half-Life: The half-life of a drug models exponential decay. If a drug concentration halves every 4 hours, after t hours, the concentration A can be modeled as A = C * 2^(-t/4), where C is the initial concentration. Negative indices are crucial here.
Audio narration — reads aloud, works offline

In your own words, summarise the main idea of this lesson.