SOLUTION: Solve. 9x^4-18x^2+5=0 Would someone please help me solve this problem. I come up with various answers, and I know that there is only one set of answers. Thank you very much.

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equation Customizable Word Problems -> SOLUTION: Solve. 9x^4-18x^2+5=0 Would someone please help me solve this problem. I come up with various answers, and I know that there is only one set of answers. Thank you very much.      Log On


   

Question 468702: Solve.
9x^4-18x^2+5=0
Would someone please help me solve this problem. I come up with various answers, and I know that there is only one set of answers. Thank you very much.
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
9x^4-18x^2+5=0
rewrite as:
9x^4-15x^2-3x^2+5=0
group terms:
(9x^4-15x^2)-(3x^2-5)=0
3x^2(3x^2-5)-(3x^2-5)=0
(3x^2-5)(3x^2-1)=0
.
x = {sqrt(5/3), sqrt(1/3)}
rationalize denominators:
x = { sqrt%2815%29%2F3%29, sqrt%283%29%2F3 }