Changing equation to standard form

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Homework Statement



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

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?
 
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nevermind, i got it
 
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:
 
renob said:

Homework Statement



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


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, [itex]-(x^2+ 2x- 2)= -x^2- 2+ 2[/itex], not [itex]x^2- 2x+ 2[/itex].
[itex]x^2- 2x+ 2= (x- 1)^2+ 1[/itex].

but that just makes the 2 negative.

How should I go about converting the second equation?
 
hmm did i make a mistake somewhere? Where did the [itex]x^2- 2x+ 2[/itex] come from haha::rolleyes:
 
it comes out to be -(x+1)^2+3
 
HallsofIvy said:
No, [itex]-(x^2+ 2x- 2)= -x^2- 2+ 2[/itex], not [itex]x^2- 2x+ 2[/itex].
[itex]x^2- 2x+ 2= (x- 1)^2+ 1[/itex].

I think you misread the second equation