Question 251202: solve for x and express the solution in intervals.x^3-3x+2<=0
Answer by drk(1908)   (Show Source):
You can put this solution on YOUR website! We can factor x^3-3x+2<=0 into
(X+2)(X-1)^2 <= 0
Now we would look at where X+2 is +, 0, and -.
We see that it is negative for all x < -2, zero at x = -2, positive at X > -2.
Now we would look at where(X-1)^2 is +, 0, and -.
We know that any number squared can = 0 or be positive. We see that the answer is zero if x = 1, and positive every where else.
We want answers that are either zero or negative. This occurs on the interval X <=-2.
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