SOLUTION: x^4-2x^2-8

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Question 8086: x^4-2x^2-8
Answer by srinivas123(23) About Me  (Show Source):
You can put this solution on YOUR website!
hope this question is x^4-2x^2-8 =0
let x^2 be y .
Then,
y^2-2y-8=0
y^2-4y+2y-8=0
y(y-4)+2(y-4)=0
(y+2)(y-4)=0
----- > y=-2 or y=4
----- > x^2= -2 or x^2 = 4
----- > x= sqr root of -2 or x = +/-(plus or minus)2.