Question

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

Answer 1

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