SOLUTION: find all zeroes. f(x)=25x^8-26x^4+1

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Question 1091092: find all zeroes.
f(x)=25x^8-26x^4+1
Answer by CubeyThePenguin(3113) About Me  (Show Source):
You can put this solution on YOUR website!
Let x^4 = y.

f(x) = 25y^2 - 26y + 1
= (25y - 1)(y - 1)

x^4 = 1 ---> x = 1, -1, i, -i
x^4 = 1/25 ---> x = +sqrt(5)/5, -sqrt(5)/5, i%2Asqrt%285%29%2F5, -i%2Asqrt%285%29%2F5

Usually you will only need the real solutions, but I have added the complex solutions just in case.