Continuous functions

1. Feb 8, 2010

hallowon

1. The problem statement, all variables and given/known data

g(x)={x+3, x[STRIKE]=[/STRIKE]3
{2+$$\sqrt{k}$$ , x=3

find k if g(x) is continuous
2. Relevant equations

3. The attempt at a solution

I have no idea how to begin, but drawing the first part on a cartesian plane.

2. Feb 8, 2010

Gunthi

Re: Continuity

Are you sure g(x) is well defined? Because if it is you just have to get a k that doesn't cause a contradiction...

3. Feb 8, 2010

Seb97

Re: Continuity

Hi Hallowon
Is the first part not x+3, and x not eual to 3? YA

To say that g(x) is continous at y=3 is to say that

lim as x goes to 3 = f(3)

In our case the left hand side is equal to x + 3= 3+ 3=6

while the right hand side is equal to 2 + rootk but this must equal the left hand side for it to be continous so we have

6= 2 + rootk
4=rootk
16=k

Hope this helps. Sorry I had to give solution.haha

4. Feb 8, 2010

hallowon

Re: Continuity

ahh thank you i didn't event hink to make them equal to one another. Looks like i have a long way to go for continuity -_-

5. Feb 8, 2010

Seb97

Re: Continuity

Ah your welcome. Its actually not that bad. I havent really covered it but if you have any futher questions dont hesitate to ask. If you look on you tube they might have something on continuity. It would be much more helpful seeing someone go through it rather than reading from some black and white text book.

6. Feb 8, 2010

Redbelly98

Staff Emeritus
Re: Continuity

Moderator's note:

Giving out solutions to homework problems is against the guidelines of Physics Forums. Please review the section on Homework Help https://www.physicsforums.com/showthread.php?t=5374".

Last edited by a moderator: Apr 24, 2017