Question

lf $\underset{x\to 5}{lim}f\left(x\right)=4$ then $\underset{y\to \frac{1}{3}}{lim}f\left(15y\right)$ is equal to

• A. $1$
• B. $\frac{1}{3}$
• C. $\frac{4}{3}$
• D. $4$

Answer 1

Answer: (D)

$4$

Given,
$\underset{x\to 5}{lim}f\left(x\right)=4$

$\underset{y\to \frac{1}{3}}{lim}f\left(15y\right)$

$=\underset{15y\to 5}{lim}f\left(15y\right)$

........... Consider $15y=x$

$=\underset{x\to 5}{lim}f\left(x\right)$

$=4$