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finding a logarithm
Is there a mistake in the video on finding a logarithm explanation, or am I wrong? Pasan is saying at 4:29 "So if I say log to the base 2 of 8 = 3, I'm basically saying the opposite of an exponent. Instead of saying how many times do I have to multiply this value, I'm asking, how many times do I have to divide 8 by 2 to get the value 3 (he is saying 1 for some reason though)?"
I agree with everything except the very last sentence. I don't think it will be correct to say that we can calculate a logarithm by finding how many times we have to divide its argument (in our case 8) by its base (in our case 2) to get the answer. The correct answer is 3, but we won't be able to achieve it with division by 2: I. 8 : 2 = 4 II. 4 : 2 = 2
Please correct me if I am wrong on that. (P.S. Sorry, I don't know how to write subscripts here in the forum)
Jennifer NordellTreehouse Teacher
Hi there, Veronika Post! He is correct. He's saying that you have to determine how many times 8 will be divided by 2 to get to the value of one, not two.
Here's a quote from 4:40 in the video:
I'm asking, how many times do I have to divide 8 by 2 to get the value 1?
8 / 2 = 4 // 1 division 4 / 2 = 2 // 2 divisions 2 / 2 = 1 // 3 divisions
When determining the logarithm we are dividing backwards to a value of one. Note that I'm using
^ to denote "to the power of":
- 2^0 = 1
- 2^1 = 2
- 2^2 = 4
- 2^3 = 8
Hope this helps!