Determinati valoarea numarului a cu prprietatea lim x->infinit (ax+3)/2x+5=4

Răspuns :

[tex]\displaystyle\limit\lim_{x\to\infty} \dfrac{ax+3}{2x+5}=\displaystyle\limit\lim_{x\to\infty} \dfrac{x\left(a+\frac{3}{x}\right)}{x\left(2+\frac{5}{x}\right)}=\frac{a}{2}\\
\text{Prin urmare:}\\
\dfrac{a}{2}=4\Rightarrow \boxed{a=8} [/tex]