SOLUTION: x^3 - 5x^2 +8x-4=0 Answer is 1 or 2 but having difficulty figuring out how to solve this other than trial and error.

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Question 819654: x^3 - 5x^2 +8x-4=0
Answer is 1 or 2 but having difficulty figuring out how to solve this other than trial and error.

Answer by tommyt3rd(5050) About Me  (Show Source):
You can put this solution on YOUR website!
We could use DesCartes rule of signs, to show 3 positive roots, then the rational zeros test to narrow the choices. Finally using synthetic division to get them. However, since we know them and they are rational, let's factor.

x%5E3+-+5x%5E2+%2B8x-4=%28x%5E3-4x%5E2%2B4x%29-%28x%5E2-4x%2B4%29
Then...
x%28x%5E2-4x%2B4%29-1%28x%5E2-4x%2B4%29=%28x-1%29%28x-2%29%5E2