# Help on graph

1. Nov 6, 2007

### poohbear1986

ok i was graphing y=-e^x e=2.1783 and i got this up and down line growing from negative to positve, i have no clue what the hell im looking at, ive attached what i got tell if im right or wrong, point in the right direction if you could

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2. Nov 6, 2007

### JasonRox

Take the graph of e^x and flip it upside down.

3. Nov 6, 2007

### poohbear1986

thank you that was driving me nuts

4. Nov 6, 2007

### Integral

Staff Emeritus
The graph you have posted is NOT $- e^x$

5. Nov 7, 2007

### HallsofIvy

Staff Emeritus
Since you don't say HOW you got that graph, there's not much more we can tell you!
(It looks to me something like y= excos(x).)

6. Nov 7, 2007

### Moo Of Doom

It looks to me like a naive attempt at (-e)^x, judging from the oscillations. Of course, the points between the integers are all wrong. That MAY have been the logic behind it, but I don't know...

7. Nov 7, 2007

### Diffy

poohbear, there is still some confusion. Are you trying to graph (-e)^x or -(e^x). There is a big difference, and writing -e^x is slightly ambiguous (although it implies the latter of the two I wrote).

Moo Of Doom, you are right it looks like (-e)^x (with connecting lines drawn in the undefined parts) but when x is 2 f(x) should be around 7.4 and in his document 4 < f(2) < 6 which actually satisfies neither of the two possibilities mentioned.

8. Nov 7, 2007

### Moo Of Doom

I thought it was odd too, but when you look at the original post, he says

and 2.17822 is about 4.74. I think he mistyped his value for e when he plotted the points as well. Makes everything pretty confusing, doesn't it?