Math Help - matlab plot function

1. matlab plot function

Code:
x1=-10:.1:10;
y1=exp(x1) - (7*x1);
plot(x1,y1);
The graph that i get looks very wrong

How can i resolve this issue

2. Originally Posted by AUCC
Code:
x1=-10:.1:10;
y1=exp(x1) - (7*x1);
plot(x1,y1);
The graph that i get looks very wrong

How can i resolve this issue

The graph IS correct. But give a look at the scale on the vertical axis... Problem is that for x=10, $\exp(x)$ is huge, so that we can't even distinguish $-70$ (which would be the value for x=-10, approx.) from 0.

"Solution" is to adjust the extent of the values x is assumed to take: choose x1=-10:.1:5 instead, for instance.

3. Well i didn't focus on the shape of the graph for positive values for x

For negative values of x the graph looks very very wrong

at x values lesser than zero the graph should go in the upward direction but the graph that mat-lab gives me lies on the x axis.