Extended data:

Precautions:

The base of 1 and logarithm should be a positive number not equal to 1; Because the real number of logarithm can only be positive.

2. The logarithm of the difference is not equal to the difference of logarithms (equation 6 in the above figure), and the logarithm of 1 is 0.

3. When using the formula with logarithm as the base, the logarithms with different bases can be changed into logarithms with the same base. For example, first unify the base into an appropriate number as the base. If the unified base is 10, it is an ordinary logarithm.

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