Easy Functions question?

This is a question i found in my maths text book that barely has any explanations on it:

sketch the graph for:

f(x) = x + 1 if x>=1
2 if x < 1

Reverance2010-03-17T03:43:01Z

Favorite Answer

Well, the graph for y=x is just a straight line (going diagonally from them bottom left to top right).
The graph y=x+1 is exactly the same but the line is shifted 1 unit up and has the intercepts y=1 and x=-1. However, there is a domain specified which I think what you mean is x is greater than/equal to 1. So the graph would start with a black dot at x=1 (so the co-ordinates are [1,2]), and then continue up. You don't plot the the bottom part of the graph as the domain says only for x-values of 1 and over.
Now for the second question, you do the pretty much the same thing. But, the difference is that instead of lesser than/equal to, the domain is only asking for lesser than. So, you don't put a black dot, but a small circle instead (like an outline of the dot), then you plot the graph going downwards (all x-values that are less than 1 not including 1).

Wish i could've drawn it, would've been way easier.
Hope that helps :P