- #1
theintarnets
- 64
- 0
Homework Statement
First find all rational zeros of f, then use the depressed equation to find all roots of the equation f(x) = 0.
f(x) = x^3 + 5x^2 - 8x + 2
Homework Equations
The Attempt at a Solution
Possible rational zeros: 2, -2, 1, -1
Synthetic division:
1 | 1 5 -8 2
_____1 6 -2
=============
1 6 -2 0
Quotient: x^2 + 6x - 2
Factored: (x + 3)^2 - 11
I would think that the answer would just be x = -3 ± √(11) but the answer in the book says: {1, -3 ± √(11)}
Where'd the 1 come from?