Greetings to any and all that might read this. I am a 12-th grade student from Portugal and, here, it is not allowed for us to solve limits through L'Hôpital's Rule at this level (in fact, it isn't even taught, though we learn derivatives as well...), which places me (us) in a somewhat difficult position regarding the evaluation of some limits. Specifically, I've come across two particular limits that, somehow, have proven quite elusive to solve without recurring to L'Hôpital's Rule. Namely,
$$\lim _{x\to -2}\left(\frac{e^{x+2}-1}{\ln\left(7x+15\right)}\right)$$
and
$$\lim _{x\to 0}\left(\frac{\ln\left(x+1\right)-x}{x^2\left(1-x\right)} \right)$$
Through L'Hôpital's Rule, I've been able to determine that the first limit should yield $\frac{1}{7}$ and the second $-\frac{1}{2}$, but I haven't been able to reproduce this results without resorting to L'Hôpital's Rule, which is the way they demand the exercise to be solved. I've tried several variable substitutions, but all no avail; I might be missing something quite obvious, which is a mistake I often make, but I seem not to be able to solve them. In that sense, I was expecting that the Math community could help me with this problem.
I thank you in advance for your answers and I apologize for any inconvenience my question might represent.
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