SOLUTION: what is 3^-x = x^3 + x

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Question 1067775: what is 3^-x = x^3 + x
Found 2 solutions by Edwin McCravy, rothauserc:
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
what is 3^-x = x^3 + x
There is no algebraic method for solving an equation in which
a variable appears in an exponent and also in a base of an
exponent.

Such equations can only be solved by some iterative process or
by using technology (which uses iterative processes):

Answer: 0.4798223224 

Edwin

Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
3^-x = x^3 + x
:
graph 3^(-x), the red line, and x^3+x. green line - where they intersect is solution for x
:
+graph%28+400%2C+300%2C+-2%2C+2%2C+-10%2C+10%2C+3%5E%28-x%29%2C+x%5E3%2Bx%29+
:
x is approximately 0.48
: