The problem is attached
the answer is d.
Note that for large values of \(x\) the value of \(e^{5/2x}\) gets arbitrarily small so we can use a taylor expansion to simplify this expression. Note that: \[\Large e^x = 1 + x + \frac{x^2}{ 2}+ \dots \] such that: \[\Large e^{\frac{5}{2x}}\sim 1+ \frac{5}{2x} \] We drop the higher order approximations because they vanish fast to zero, plugging this back in our equation gives: \[\Large \lim_{x \to \infty} xe^{\frac{5}{2x}}-x=x \left( 1 + \frac{5}{2x}\right)-x = \lim_{x \to \infty} \frac{5}{2}=\frac{5}{2} \]
Those problems are very cool Professor @eliassaab, keep them coming.
well notice$$x(e^{5/2x}-1)=x\left(\frac5{2x}+\frac12\left(\frac5{2x}\right)^2+\dots+\frac1{n!}\left(\frac5{2x}\right)^n+\dots\right)=\frac52+x\cdot(\dots)$$
@Spacelimbus , I am glad your enjoying them. I posted another one.
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