Question
If x 4 – 83x 2 + 1 = 0, then
find the value of x 3 - x -3 can be:Solution
x 4 – 83x 2 + 1 = 0
So, (x 2 + 1/x 2 ) = 83
So, (x – 1/x) = √(83 – 2) = 9
So, x 3 - x -3 = 729 + 3 × 9 = 756
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