Math Is Fun Forum

mrpace

Member

Registered: 2012-08-16

Posts: 88

Help with this weird question??

If f(x) = x^2  if x is greater than or equal to zero.
         = 1 if x is less than zero

then find an expression for the following:

[f(h) - f(0)] / h

h can't equal zero obviously

I don't know how to do these problems so any help is appreciated.

Sorry for the lack of latex...i tried to learn but i don't get it.

Bob

Administrator

Registered: 2010-06-20

Posts: 10,643

Re: Help with this weird question??

hi mrpace

Because the definition comes in two parts, the answer will too.

x ≥ 0 :

x < 0

You could argue that f(0) is undefined when x < 1 and therefore this second answer cannot be determined but I don't think that is intended.

I have used Latex.  If you click on the expression above you'll get a window that shows the code for this.  You have to add at the start square brackets math, and complete the code with square brackets /math

Thus:

There's a tutorial to get you started here:

http://www.mathisfunforum.com/viewtopic.php?id=4397

The first few posts in that thread will be enough to get you started.  There's an editor at:

http://latex.codecogs.com/eqneditor/editor.php

Bob

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

mrpace

Member

Registered: 2012-08-16

Posts: 88

Re: Help with this weird question??

hi mrpace

Because the definition comes in two parts, the answer will too.

x ≥ 0 :

x < 0

You could argue that f(0) is undefined when x < 1 and therefore this second answer cannot be determined but I don't think that is intended.

I have used Latex.  If you click on the expression above you'll get a window that shows the code for this.  You have to add at the start square brackets math, and complete the code with square brackets /math

Thus:

There's a tutorial to get you started here:

http://www.mathisfunforum.com/viewtopic.php?id=4397

The first few posts in that thread will be enough to get you started.  There's an editor at:

http://latex.codecogs.com/eqneditor/editor.php

Bob

Great. I see how it works now. Thanks a lot.