SOLUTION: I have tryed these four questions a few times each and have come up with dif answers each time!! I know that I am missing something and was wondering if you could help!! These ar

Algebra.Com
Question 170212: I have tryed these four questions a few times each and have come up with dif answers each time!! I know that I am missing something and was wondering if you could help!! These are practice questions for an upcoming exam! I have to be able to get consistant answers!! Please help if you can!! Thank you..
(x^2 -3)^2 + (x^2 -3) -2=0
"^" indicates "squared"

Found 2 solutions by jim_thompson5910, scott8148:
Answer by jim_thompson5910(35256)   (Show Source): You can put this solution on YOUR website!
Let . So this means that


So the equation simplifies to




Start with the given equation.


Notice we have a quadratic equation in the form of where , , and


Let's use the quadratic formula to solve for z


Start with the quadratic formula


Plug in , , and


Square to get .


Multiply to get


Rewrite as


Add to to get


Multiply and to get .


Take the square root of to get .


or Break up the expression.


or Combine like terms.


or Simplify.


----------------------------------------------------------------


Now remember, we let .


Go back to the first equation


Plug in


Add to both sides.


Combine like terms.


Take the square root of both sides.


or Break up the "plus/minus" to form two equations.


or Take the square root of to get .



So the first two solutions are or .


----------------------------------------------------------


Now move onto the second equation


Plug in


Add to both sides.


Combine like terms.


Take the square root of both sides.


or Break up the "plus/minus" to form two equations.


or Take the square root of to get .



So the next two solutions are or .


=========================================================================

Answer:


So the solutions are

, , or


Note: the order of the solutions does not matter.

Answer by scott8148(6628)   (Show Source): You can put this solution on YOUR website!
this is a quadratic equation with (x^2 -3) as the variable

imagine if (x^2 -3) is m, then m^2 + m - 2 = 0, which factors to (m+2)(m-1)=0

factoring __ [(x^2 -3)+2][(x^2 -3)-1]=0

x^2 -3 +2 = 0 __ x^2 -1 = 0 __ factoring __ (x+1)(x-1)=0 __ x=1, x=-1

x^2 -3 -1 = 0 __ x^2 -4 = 0 __ factoring __ (x+2)(x-2)=0 __ x=2, x=-2

RELATED QUESTIONS

I have worked this problem a few times and i keep comming up with different answers each... (answered by Alan3354)
This is homework and I have tried I keep coming up with 35 as the answer but different... (answered by stanbon)
I am having trouble with this problem, I have come up with a couple different answers.... (answered by longjonsilver)
A product costs $7 for 20 lbs. How much is that in cents per ounce? I have worked... (answered by stanbon)
-x + y = 4 2x - 5y = -14 I am completely stuck on how to go about doing this... (answered by Fombitz,josmiceli)
find the eact value is 0 (answered by venugopalramana)
I am going through an assignment and my answers - I have worked out the answer to the... (answered by stanbon,rothauserc)
I have tried these problems a few times and cannot come up with a solution...help! a)... (answered by jim_thompson5910)
I have worked this problem several times and come up mwith different answers i think i am (answered by checkley77)