solving exponential equations graphically
posted by Jen on .
e^(3-2x) = 4
How do I solve this graphically? Thanks.
Make a graph of e^(3 - 2x) vs x for various values of x from 0 to 2. The answer will be in that interval. Where the graph crosses f(x) = y = 4, read off the value of x. That will be the answer.
When x = 0, e^(3-2x)= e^3 = 20.09
When x = 0.5, e^(3-2x) = e^2 = 7.389
When x = 1, e^(3-2x)= e = 2.718
The answer f(x) = 4, will be between x = 0.5 and 1. Try x=0.8! It's pretty close to the right answer.