finding parameters so that ∞ - ∞ = 0

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I am currently doing some old math exams and was wondering whether my solution for the given question was appropriate (see picture)

see problem here

for me it just feels like the point where I put together both limits bc the functions are continous I am doing something wrong, especially because the problem explicitly does not have a limit in front of the summand given by β*e^x+γ

Really appreciate your help guys, and sorry I am not yet able to write in LaTex.

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$$\lim_{x\to+\infty}\left(\frac{2e^{3x}}{e^{2x}-1}-\beta e^x +\gamma \right)=0 $$ Find the common denominator of your expression: $$\frac{2e^{3x}-\beta e^{3x}+\beta e^x+\gamma e^{2x}-\gamma}{e^{2x}-1} $$ If $2-\beta\neq0$, the limit it $+\infty$ since $e^{3x}$ grows faster than $e^{2x}$; so you must have $\beta=2$.

If $\gamma\neq0$, the limit is $\gamma$ , hence you must have $\gamma=0.$