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Digital Literacy

Introduction to Logarithms

Introduction to Logarithms

Khan Academy · YouTube
Audio narration — reads aloud, works offline

Transcript

[0:00] An index, or power, tells us how many times a number is multiplied by itself, like two to the power four. [0:40] When we multiply powers of the same base we add the indices; when we divide we subtract them. [1:25] Standard form writes a number as a value between one and ten, multiplied by a power of ten, such as 3.2 times ten to the five. [2:10] A logarithm answers the question: to what power must we raise ten to get this number? [2:55] Because logs turn multiplication into addition, they were the calculators of the past and still build deep number sense today.

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