@Michele_Laino
hint: evaluate this limit, please: \[\lim _{x \rightarrow \infty}\frac{ e ^{x+3} }{ e ^{x} }=...\]
another hint: please note that: \[\frac{ e ^{x+3} }{ e ^{x} }=e ^{3}\] so?
it is B!
no, because: \[\lim _{x \rightarrow +\infty}\frac{ e ^{3x} }{ e ^{x} }=\lim _{x \rightarrow +\infty}e ^{2x}=+\infty\]
oh so it is C?
no, because: \[\lim _{x \rightarrow +\infty}\frac{ e ^{2x} }{ e ^{x} }=\lim _{x \rightarrow + \infty}e ^{x}=+\infty\]
yes!, because: \[\lim _{x \rightarrow +\infty}\frac{ e ^{x+3} }{ e ^{x} }=e ^{3}\neq 0\]
hint: \[\frac{ x+sinx }{ x }=1+\frac{ \sin x }{ x }\] so?
they are the same rate!
yes, because if x>0, since x---> +infinity, we have: \[-\frac{ 1 }{ x }\le \frac{ \sin x }{ x }\le \frac{ 1 }{ x }\] since: \[-\frac{ 1 }{ x }\rightarrow 0, \frac{ 1 }{ x }\rightarrow 0\] when x--->+infty, we have: \[\lim _{x \rightarrow +\infty}\frac{ \sin x }{ x }=0\] and: \[\lim _{x \rightarrow +\infty}\left( \frac{ x+ \sin x }{ x } \right)=0\]
of course, the same result we will get in the case x--->-infinity
namely: \[x \rightarrow -\infty\]
so it is C (:
oops... \[\lim _{x \rightarrow +\infty}\left( \frac{ x+ \sin x }{ x } \right)=1\]
wait is it c?
yes! it is C
thank you !!!!
thank you! :)
thank you !!!!
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