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1. Find the positive constants a and b such that x^4 + 9/x^4 = (x^2 - a/(x^2))^2 + b for all non zero values of x.

Damn!!!!! help.
2. (Original post by Dines)
Find the positive constants a and b such that x^4 + 9/x^4 = (x^2 - a/(x^2))^2 + b for all non zero values of x.

Damn!!!!! help.
Is that ?

Expand and compare coefficients.
3. (Original post by Kvothe the arcane)
Is that ?

Expand and compare coefficients.
You there? How to expand. Just give me a starting hint.
4. (Original post by Dines)
You there? How to expand. Just give me a starting hint.
Expand the bracket as you would normally. .
Except in this case, and .

5. (Original post by Dines)
How to expand this
If you know how to expand brackets normally, then this is no different, if not see below
Spoiler:
Show

if it makes it easier say that u=a/x^2
So then you would need to expand (x^2 -y)
Then you can just substitute in the value of u later on
6. (Original post by Kvothe the arcane)
Expand the bracket as you would normally. .
Except in this case, and .
Wouldn't that be
Spoiler:
Show

?
7. (Original post by Kvothe the arcane)
Expand the bracket as you would normally. .
Except in this case, and .
Mu should be a/x^2
8. (Original post by thefatone)
Wouldn't that be
Spoiler:
Show
?
Spoiler:
Show

yes.
9. (Original post by Kvothe the arcane)
Spoiler:
Show

yes.
lol you edit mine aswell xD

guess i should put in a spoiler xD
a=3
b=6

Thank you.

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