Finding roots?

Question

How do you find all possible roots of this equation and how do you find zeros? Im home sick with mono with no one to ask.
2x^4-x^3 -2x^2+5x+1

it is one of those synthetic division equations

Answer 1

DesCartes rule of signs tells you that you have two real roots and two complex imaginary roots.

Try values of x. Note that f(-2) = 12 and f(-1) = -3
Thus a root must lie between -2 and -1 because F(x) changed from + to - .

Again f(0) = 1 so there must be a 2nd root between -1 and 0.

Now you can us Newton's method to narrow down the location of each root to what ever degree of accuracy you desire.

You could then find the complex roots by using long division and the quadratic formula.

Answer 2

This is a fourth degree equation, then, it has 4 roots. The solution for this kind of equation is not easy. I think the only way is using numerical calculus using a computer.

Answer 3

supposing this expression = 0 The possible rational roots are+-1 ,+-1/2 which are not so
x=-0.187238 and x= -1.369168 teh other are complex conjugates x=1.028446+- i *0.942142

Answer 4

Would like to help, but what you presented is not an equation, does not equal anything?
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