WEBVTT

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Here is the problem: Evaluate log base 4 of 8.

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Evaluate the logarithm of 8 with base 4.

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Ask: what power of the base gives the number?

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Write both numbers as powers of the same prime factors. Comparing prime exponents shows 8 equals 4 to the power 3 over 2).

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So the answer is log 4(8) equals 3 over 2.

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4 raised to 3 over 2 gives 8 exactly.

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Check: 4 to the power 1.5 approximately 8.