Define range of y axis, instead of just x axis?

edit

plot(2*x+1, (-5,5),ymin=-4,ymax=4) This worked, thanks. What if the given the function: y^2 = x How would 1 plot it? I was able to do: plot(sqrt(x)) But as you know, one can't find the sqrts of negative number; so only the top half of the graph was displayed. The bottom half wasn't displayed :

Your best option here is to use `implicit_plot`. Try `implicit_plot(y^2==x,(x,-5,5),(y,-5,5))`.

y^2 =x is not a function; it fails the vertical line test. You could also try A=plot(sqrt(x),(x,0,1)) B=plot(-sqrt(x),(x,0,1)) show(A+B,xmin=-1,xmax=1)

Or you could do `var('y'); plot(y^2,(y,-5,5),axes_labels=['$y$','$x$'])` if you wanted to be tricky - see [this link](http://sagecell.sagemath.org/?q=73417d65-fe8a-43f5-90a5-b9105813a02d).

@bxdin - even better than implicit_plot, you can use parametric_plot. See

• Ask Sage question 51005: How to correctly plot x^(1/3).

This is because ymin, ymax are actually an option to show(). The documentation in plot() links to the documentation of show() for this and many other options. It also mentions ymin/ymax explicitly in a special "Note" section.