M HYPE SPLASH
// news

Find the limit of $f(x)$ as $x$ approaches $3$ from the left

By Michael Henderson
$\begingroup$

$$f(x)=\begin{cases} {0} & \text{if $x<3$} \\x+1 & \text {if $3\le{x}\le4$}\\ 5 & \text{if $x>\ 4$} \\ \end{cases}$$

As it asks me to approach $3$ from the left I concluded that the answer would be $0$ as if it is $x<3$, $f(x)=0$. This seems too easy however so I would like to know if I did something wrong and what I can correct if I did do this question incorrectly.

$\endgroup$ 1

1 Answer

$\begingroup$

You are correct. $$lim_{x->3^{{-}}}f(x)=0$$

Remember that $x%$ approaches $3$ but never reaches it.

Thus $x$ is always in the domain of the part if $x < 3$

Note that you are only correct because from the left

Since the limit from the right is equal to $4$. The limit actually doesn't exist. But the 1 sided limits do.

$\endgroup$ 2

Your Answer

Sign up or log in

Sign up using Google Sign up using Facebook Sign up using Email and Password

Post as a guest

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy