# Urgent basic calculus help needed...(this wasn't covered in class notes!)

• Mar 25th 2008, 07:48 PM
Chuck61686
Urgent basic calculus help needed...(this wasn't covered in class notes!)
1) Given f(x) = 3x + 2, where is the function increasing?

2) Given f(x) = x-2 / 3
The "/" is meant to denote a fraction, x-2 over 3
-what is the vertical asymptote?
-what is the horizontal asymptote?

• Mar 25th 2008, 08:09 PM
o_O
1. What does the graph of this look like? You should be able to figure out quickly that it's ALWAYS increasing. Why? Look at f'(x)

2. $f(x) = \frac{x-2}{3}$
Vertical asymptote: Is there even any x values that f(x) cannot have (i.e. lead to a division of 0 or anything like that?)?

Horizontal asymptote: You should tell what type of graph this is and deduce if there are any. But nonetheless, what is: $\lim_{x \to \pm \infty} f(x)$?
• Mar 25th 2008, 08:29 PM
Chuck61686
Quote:

Originally Posted by o_O
1. What does the graph of this look like? You should be able to figure out quickly that it's ALWAYS increasing. Why? Look at f'(x)

2. $f(x) = \frac{x-2}{3}$
Vertical asymptote: Is there even any x values that f(x) cannot have (i.e. lead to a division of 0 or anything like that?)?

Horizontal asymptote: You should tell what type of graph this is and deduce if there are any. But nonetheless, what is: $\lim_{x \to \pm \infty} f(x)$?

Thanks for the input, this is what I came up with:

For (1) I came up the function is increasing at negative infiniti.
For (2) I came up with where is no vertical asymptote and no horizontal asymptote.

• Mar 25th 2008, 09:07 PM
o_O
2 is correct.

For the first one, what kind of graph is it? What is f'(x)? If a function is monotonically increasing, what property should f'(x) have?
• Mar 25th 2008, 09:12 PM
Chuck61686
Quote:

Originally Posted by o_O
2 is correct.

For the first one, what kind of graph is it? What is f'(x)? If a function is monotonically increasing, what property should f'(x) have?

Wait...f'(x) is negative, therefore it is increasing NOWHERE?
ps - please excuse my stupidity..I haven't taken a math course in years, I'm only doing this so I can get into med school.
• Mar 25th 2008, 09:52 PM
a.a
a reali easy way to look at #1 is that its a striaght line with a +ve sope.. so that means it is increasing

also f'(x)= 3... a +ve number..