Create a MATLAB script that generates x-values from -2 to 2 using linspace with 200 value in plot. Define four different y-values as follows:

1. y1=cos(x)
2. y2=e^((x^2/2))
3. y3=1/(1+x^2)
4. y4=sqrt(1+x^2)

Plot these four curves on the same graph using different line styles and colors. Add appropriate labels for the x-axis and y-axis, a title for the plot, and a legend.