Question 1006106
<pre>
Did you not mean for any of the < 's or the > to be &#8806; or &#8807;? 
Without them the function is not defined at x=4 or at x=-1.  There are
only open circles at x=4 and x=-1.  For there to be an answer to this problem,
one of those open circles would have be closed like this &#9679; at x=4, but they
are all open circles, &#9675;, since you have only < and >, not &#8806; or &#8807;.   

{{{"f(x)"}}}{{{""=""}}}{{{system( matrix(3,3,

-3,",",x<-1,
1,",",-1<x<4,
2x,",",x>4))}}}

This has the graph:

{{{drawing(280,400,-7,7,-5,15,graph(280,400,-7,7,-5,15),

line(-10,-3,-1.2,-3),line(-.8,1,3.8,1),line(4.1,8.2,10,20),
circle(-1,-3,.2),circle(-1,1,.2),circle(4,1,.2),circle(4,8,.2) )}}}

This function is not defined at x=4.

Edwin</pre>