# Math Help - Mathematica 7.0, plotting x*sin(x), weird looking graph

1. ## Mathematica 7.0, plotting x*sin(x), weird looking graph

The command I'm using is
Code:
Plot[{x*Sin[x]}, {x, -80 Pi, 100 Pi}]
and I get this weird result. Look at x= approx -80 and 130.

Some other similar intervals involving pi also give weird results looking almost like that. There are at least four options:

1. I'm too dumb to realize it's supposed to look like that
2. My computer is broken
3. Mathematica is broken
4. It's not a bug, it's a feature.

So my question is, does this happen to anyone else using Mathematica (v7.0.1.0)?

2. Originally Posted by mathpath
The command I'm using is
Code:
Plot[{x*Sin[x]}, {x, -80 Pi, 100 Pi}]
and I get this weird result. Look at x= approx -80 and 130.

Some other similar intervals involving pi also give weird results looking almost like that. There are at least four options:

1. I'm too dumb to realize it's supposed to look like that
2. My computer is broken
3. Mathematica is broken
4. It's not a bug, it's a feature.

So my question is, does this happen to anyone else using Mathematica (v7.0.1.0)?
need to specify more sampling points:

Code:
Plot[{x*Sin[x]}, {x, -80 Pi, 100 Pi}, PlotPoints -> 200]
or maybe fewer like 100 or so. Whatever it takes to get it right.

3. Thanks! That fixed it!
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