# Math Help - Exponential Question

1. ## Exponential Question

I am not positive this is the correct spot for this question ( it is an Algebra question but it was not given in the context of an Algebra class. I am currently working my way through Michael Spivak's book "Calculus"). Here is the question:

$

x + 3^x<4
$

Now just by looking at it, I can see that the answer has to be x<1 but I don't see how I could show that mathematically. Any insights would be appreciated.

Dag

2. Hi

$f(x) = x + 3^x$ is an increasing function and f(1)=4 therefore for all x<1 f(x)<4