Indentify the typer of conic section and its vertices&foci. Calc II

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Homework Statement



Identify the type of conic section whose equation is given as y^2+2y=4x^2+3
Also find its vertices and foci
(y-k)^2/a^2-(x-h)^2/b^2=1

Homework Equations



I believe when you have x&y ^2 in an equation it can be either an ellipse or a hyperbola but if the signs are opposite it is a hyperbola. vertices ± a from center, foci ± c from center.

The Attempt at a Solution


I begin by rewriting the equation y^2+2y=4x^2+3 as
y^2+2y-4x^2=3 thus allowing me to recognize that the powers or x/y ^2 are opposite, and thus the type of conic section is a hyperbola.
I complete the square for the y(s) of the equation which gives me (y+1)^2-1
and I now rewrite the equation as (y+1)^2-4x^2=3+1, (y+1)^2-4x^2=4
there is no way of completing the square for 4x^2 however since I know the equation is in the form (x-h)^2 I will rewrite -4x^2 as -4(x-0)^2
I will rewrite the equation again as:
(y+1)^2-4(x-0)^2=4 and again in the form of (y-k)^2/a^2-(x-h)^2/b^2=1
as, (y+1)^2/4 - (x-0)^2/1 = 1
thus I have a^2=4, b^2=1, and a=2, b=1
I know have all the necessary things to solve for the question.
Center = (h,k)= (0,-1)
vertices are ± a from center on axis, a =2
thus vertices are (0,-1 ± 2 )
foci are ± c from center, c^2=a^2+b^2= 1+4= √5
foci: (0, -1±√5)

That is all my work/solutions for this problem.
Any help with what I may have done wrong and how to learn how to correct is, or even just saying "correct" is appreciated thank you.
 
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StudentofSci said:

Homework Statement



Identify the type of conic section whose equation is given as y^2+2y=4x^2+3
Also find its vertices and foci
(y-k)^2/a^2-(x-h)^2/b^2=1

Homework Equations



I believe when you have x&y ^2 in an equation it can be either an ellipse or a hyperbola but if the signs are opposite it is a hyperbola. vertices ± a from center, foci ± c from center.

The Attempt at a Solution


I begin by rewriting the equation y^2+2y=4x^2+3 as
y^2+2y-4x^2=3 thus allowing me to recognize that the powers or x/y ^2 are opposite, and thus the type of conic section is a hyperbola.
I complete the square for the y(s) of the equation which gives me (y+1)^2-1
and I now rewrite the equation as (y+1)^2-4x^2=3+1, (y+1)^2-4x^2=4
there is no way of completing the square for 4x^2 however since I know the equation is in the form (x-h)^2 I will rewrite -4x^2 as -4(x-0)^2
Yes, that is "completing the square" for x^2.

I will rewrite the equation again as:
(y+1)^2-4(x-0)^2=4 and again in the form of (y-k)^2/a^2-(x-h)^2/b^2=1
as, (y+1)^2/4 - (x-0)^2/1 = 1
thus I have a^2=4, b^2=1, and a=2, b=1
I know have all the necessary things to solve for the question.
Center = (h,k)= (0,-1)
vertices are ± a from center on axis, a =2
thus vertices are (0,-1 ± 2 )
foci are ± c from center, c^2=a^2+b^2= 1+4= √5
foci: (0, -1±√5)

That is all my work/solutions for this problem.
Any help with what I may have done wrong and how to learn how to correct is, or even just saying "correct" is appreciated thank you.
It all looks correct to me.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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