SOLUTION: Question about logarithms. Why is that for log(100) it is simply implied that base is 10 whereas a problem like log(8) it is not? The have the same format yet retrieve differ

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Question 915940: Question about logarithms.
Why is that for log(100) it is simply implied that base is 10 whereas a problem like log(8) it is not?
The have the same format yet retrieve different looking outcomes. Also for log(100) the log completely disappears, why is that? and for log(8) it becomes 3log2?
I am confused about this. Please help
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
The base is either understood or it is not understood. If the author believes that no confusion should occur, then he assumes the notation for the base would be unnecessary. If a chance of confusion is possible, then the author can or should indicate the base for the logarithm.

COMMON LOGARITHMS are in base ten.

log(100), has imprecise meaning unless we know which base.
log(8), has imprecise meaning unless we know which base.

You must study exponential functions before you can properly understand logarithmic functions. Each function undoes the other function.

10%5E0=1;
10%5E%28-3%29=0.001;
10%5E2=100;
Those are examples of 10%5Ex for a few simple values of x.

The meaning or description for log(r), IF the base is 10, is the the exponent which when applied to 10 gives the result of r. In case the writer wants to indicate that base ten is the intended base, notation can be log%2810%2Cr%29.
That does not appear ideally how it should. The "10" is supposed to be a subscript and must appear smaller in text size than the "log" and the "r".