Thanks, I will try that out.

I guess Maple is just not able to solve the equation in an easy way. The best solution so far is to determine the solutions from a graph and use fsolve. Are calculators clever enugh to switch to a numerical solver instead of an analytical solver? I guess so since they have no problem solving the equation.

@Doug: Thanks for your response. I found a post suggesting I used fsolve, it puzzled me that it could not return multiple results when fsolve(df=0,x,-1..3) clearly has many results.

It escapes me why maple is not able to solve a function assuming that the x value is in the interval [-1;3]. I have seen 3 different calculators solve it easily by simply telling them the lower and upper bounds of the x value.

About the multiplying of assume, that was a last minute error. I have sucessfully used assume in that manner before. Without the multiply operator and "and".

I also tried to write it like this:

assume(x<=-1.....)
solve(df = 0, x)

The response from Maple was the same as you got, but with a warning telling me that assumes might have been ignored (how helpful...).

@Pagan: Maple asks me each time i declare a function with the syntax f(x). I will try to use the -> syntax instead.

Thanks for the solutions. I will try them out.

What exactly is the reason for maple to give me such a large amount of solutions? I know there is 2 possible solutions, but I cant figure out why it would give me the rest.

That could be a solution. I'm sure that maple has a reason for creating around 20 solutions. When i enter the same eqation on my calculator (Nspire CAS) i get the two correct solutions 1.0353 and -1.0353. I would just like maple to do the same.