Let a be a positive number such that a does not equal 1, let
n be a real number, and let u and v be positive real numbers.
Logarithmic Rule 1:
Example 4: Suppose that a base is 4 and exponents are a, b, and c. We could
simplify the exponential problem by combing
the exponents and writing the problem as .
The same is true of logarithms. Suppose you wanted to simplify the
expression . You could so by writing as , providing x > 0, y>0, and Z>0..
Note: The two expressions and are equivalent expressions. Recall that equivalent expressions do not look the same but will result in the same answer is you substitute a value for x, for y, and for z in both expressions. Let's try it. Suppose x = 10, y = 15, and z = 20. Then
and
If you would like to review another example, click on Example.