Salut, ma puteti ajuta la problema numarul 1230, nu il gasesc pe acel F(x), am incercat sa derivez f(x) insa nu iasa...



Salut Ma Puteti Ajuta La Problema Numarul 1230 Nu Il Gasesc Pe Acel Fx Am Incercat Sa Derivez Fx Insa Nu Iasa class=

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[tex]\displaystyle \boxed{1230}~\lim_{x \to 0} \frac{F(x)}{\frac{f(x)}{x}}=0,~deoarece: \\ \\ \lim_{x \to 0}F(x)=F(0); \\ \\ \lim_{x \to 0} \frac{f(x)}{x}=\lim_{x \to 0} \frac{e^{x^2}}{x}= +\infty. \\ \\ \boxed{1231} \lim_{x \to \infty} \frac{F(x)}{\frac{f(x)}{x}} \\ \\ Se~stie~ca~e^x \ge x+1~\forall~x \ge 0. \\ \\ Atunci~e^{x^2} \ge x^2+1.[/tex]

[tex]\displaystyle Deci~pentru~x\ \textgreater \ 0:~ \int\limits^x_0 {e^{t^2}} dt \ge \int\limits^x_0(x^2+1) dt =\frac{x^3}{3}+x-1. \\ \\ Rezulta~\lim_{x \to \infty} \int\limits^x_0 {e^{t^2}} dt = +\infty. \\ \\ Iar~\lim_{x \to \infty} \frac{f(x)}{x}=+\infty. \\ \\ Deci~ne~aflam~in~cazul~\frac{\infty}{\infty},~si~deci~putem~aplica~L'Hospital.[/tex]

[tex]\displaystyle Limita= \lim_{x \to \infty} \frac{F'(x)}{\left(\frac{f(x)}{x} \right)'}= \lim_{x \to \infty} \frac{f(x)}{\frac{f'(x)x-f(x)}{x^2}}=\lim_{x \to \infty} \frac{x^2}{2x^2-1}= \frac{1}{2}.[/tex]