Let f(x)= x^2 -4 where x=2. find domain and range? please help

Question

Let f(x)= x^2 -4 where x<2 and 3-2x where x>=2. find domain and range? please help

anonymous · Answer

See where the expressions are zero first, then think what happens if you apply the conditions.

anonymous · Answer

well i got for domain (- $$\infty$$ , $$\infty$$ )

anonymous · Answer

Right, x can take any value cos greater than equal and less than 2.

anonymous · Answer

yeh and for range i got [-4,infinity) U [-1, -infinity). im not sure about this one so i wanted to get a second opinion

anonymous · Answer

The lowest value for x^2 -4 is going to be 4, I agree.

But what about the other? eg if you put x =5

anonymous · Answer

whoops i graphed wrong lol

anonymous · Answer

Often it's easier just to put in some "key" values near to important points just to see what's happening.

anonymous · Answer

oh just kidding i didnt....i was thinking that the graph is cut off at x=2 so i was thinking that at that value, y=-1

anonymous · Answer

happens to us all..;_)

anonymous · Answer

you can say that again lol....thanks so much for your help

anonymous · Answer

ur welcome.