SOLUTION: solve 3x³-4x-1

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Question 10270: solve 3x³-4x-1

Answer by khwang(438) About Me  (Show Source):
You can put this solution on YOUR website!
This is cubic equation not quadratic
3x³-4x-1 = 0 (missing = 0)

Factor theleft hand side:
3x³-4x-1 = 3x³- 3x- x - 1
= 3x %28x%5E2-1%29 -(x+1)
= 3x(x+1)(x-1) - (x+1)
= (x+1)%283x%5E2-3x-1%29
One root is -1 then get another two roots by using quadratic formula.
Or use synthtic division as
3 + 0-4 -1 (-1
-3 +3 +1
-----------
3 -3 -1 +0
Kenny