SOLUTION: using substitution y3^x solve the equation 3^x=2x+3^-x

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Question 1075852: using substitution y3^x solve the equation 3^x=2x+3^-x
Answer by ikleyn(52864) About Me  (Show Source):
You can put this solution on YOUR website!
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using substitution y3^x solve the equation 3^x=2x+3^-x
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In this case I will not use the substitution (since in this case it doesn't work at all).
I will use my common sense.

See the plot below, which shows the left side and the right side functions separately.



Plots y = 3%5Ex (red) and y = 2x%2B3%5E%28-x%29 (green)

Looking into the plot, you can see immediately that x = 0 is the solution.
By finding the root visually, you can check it formally: it works.


Also, the plot gives you a clue that the equation has no other roots.