SOLUTION: How do we know that the equation e^x =0 has no solution?

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Question 940336: How do we know that the equation e^x =0 has no solution?
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
e%5Ex=0
For the next step, the only option is to do the inverse function of e%5Ex which is natural log:
ln%28e%5Ex%29=ln%280%29
As you should know, we can kick the x out to the front of the natural log:
x%2Aln%28e%29=ln%280%29
The natural log of e is of course 1 leaving us with:
x=ln%280%29
Now, this is where we run into trouble because, as you will notice if you plug this into your calculator, you will receive an error message. This is because the natural log of 0 can be re-written as e%5Ea=0 where we are solving for a. However, we know e represents a constant(e=+2.71828) and any constant raised to the a power on the domain (-infinity,infinity) will be greater than 0.
There is no value for a which allows the graph to cross x-axis.

+graph%28+600%2C+600%2C+-15%2C+15%2C+-15%2C+15%2C0%2C+e%5Ex%2Ce%5Ex%29+