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renob
Sep7-09, 12:03 AM
1. The problem statement, all variables and given/known data

Sketch the region in the xy-plane that is bounded between the graphs of the given functions. Find the points of intersection of the graphs.

1) y=x^2+2x+2

2)y=-x^2-2x+2


3. The attempt at a solution

I already completed the square for equation 1):
y=(x+1)^2+1

Im having trouble completing the square for the second equation because of the negative values. I tried factoring out the negative sign:

-(x^2+2x-2)

but that just makes the 2 negative.

How should I go about converting the second equation?

renob
Sep7-09, 12:20 AM
nevermind, i got it

semc
Sep7-09, 12:21 AM
Oh well from what i can see,-x^2-2x+2 = -(x^2+2x+2) +4. so....-x^2-2x+2=-(y)+4. If you can sketch the graph for the 1st one the second one shouldn't be a problem:biggrin:

HallsofIvy
Sep7-09, 06:34 AM
1. The problem statement, all variables and given/known data

Sketch the region in the xy-plane that is bounded between the graphs of the given functions. Find the points of intersection of the graphs.

1) y=x^2+2x+2

2)y=-x^2-2x+2


3. The attempt at a solution

I already completed the square for equation 1):
y=(x+1)^2+1

Im having trouble completing the square for the second equation because of the negative values. I tried factoring out the negative sign:

-(x^2+2x-2)
No, -(x^2+ 2x- 2)= -x^2- 2+ 2, not x^2- 2x+ 2.
x^2- 2x+ 2= (x- 1)^2+ 1.

but that just makes the 2 negative.

How should I go about converting the second equation?

semc
Sep7-09, 09:49 AM
hmm did i make a mistake somewhere? Where did the x^2- 2x+ 2 come from haha::rolleyes:

renob
Sep7-09, 11:22 AM
it comes out to be -(x+1)^2+3

renob
Sep7-09, 11:24 AM
No, -(x^2+ 2x- 2)= -x^2- 2+ 2, not x^2- 2x+ 2.
x^2- 2x+ 2= (x- 1)^2+ 1.

I think you misread the second equation