Note:
If you would like an in-depth review of exponents, the rules of exponents, exponential functions and exponential equations, click on exponential function.
under Algebra.
Solve for x in the following equation.
Example 2:
Isolate the exponential term.
Divide both sides of the equation by 12
Take the natural logarithm of both sides of the equation
The exact answer is and the approximate answer is
Your exact answer may differ dependent how what logarithm you used to solve
the problem. However, all forms of the correct answer will simplify to the
same approximate answer.
When solving the above problem, you could have used any logarithm. For
example, let's solve it using the logarithmic with base 11.
Check this answer in the original equation.
Check the solution ) by substituting -5.61370563888 in the
original equation for x. If the left side of the equation equals the right
side of the equation after the substitution, you have found the correct
answer.
You can also check your answer by graphing
(formed by subtracting the right side of the original equation from the left
side). Look to see where the graph crosses the x-axis; that will be the real
solution. Note that the graph crosses the x-axis at -5.61370563888. This
means that -5.61370563888 is the real solution.
If you would like to work another example, click on Example
If you would like to test yourself by working some problems similar to this
example, click on Problem
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